1. Final Version Kequan Luu May 13-17, 2002 Micro-Arcsecond Imaging Mission, Pathfinder (MAXIM-PF) Flight Software

2. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 2  Cost Drivers  C&DH Software Functional Overview  ACS/ACE Software Functional Overview  Instrument Software Functional Overview  Required Software Development Environments  Cost Estimates  Risk Assessment  Issues & Concerns Flight Software Topics

3. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 3 Cost Drivers  Two Mission Phases of Spacecraft Constellation Configurations  Hub & Mirrorsats Attached through Mission Phase 1  Hub & Mirrorsats Detached through Mission Phase 2  Constellation Management (Comm, Science Ops, Redundancy, FDC, etc)  Smart PSE for “Extra/Better” Science Ops.

4. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 4 Flight Software C&DH Software Functions Function  Command Ingest & Distribution  R/T H-K Telemetry Transmit  Power Control (Smart PSE)  Science Ops Schedule Mgt  S/C H-K data collection  S/C & Instrument H-K data storage & playback  Science data playback  S/C & Instrument H&S monitoring  Real-time OS  File Management  S/C time maintenance & distribution (NTP)  IP/Ethernet onboard & space- space communications  IP/Ethernet onboard & space- ground communications  I/F Management Hub (1) yes (from Det) yes no yes no yes no yes Detector (1) yes (from GN) yes no MirrorSat (6) yes (from Hub) yes no yes no yes no yes

5. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 5  Sensor Data Acquisition & Processing  CSS (8)  ST (2)  IRU (1)  Accelerometer (1)  Thrusters (4)  Micro-Newton Thrusters (12)  Validate Ephemeris Update  Compute Solar Ephemeris  Compute Lunar Ephemeris  Compute Total Momentum  Estimate State Vector  Disturbance & Inertia Estimations  Adoptive Control & Formation Flying  ACE Safemode Processing  Execute Science Mode Processing  Execute Maneuver Mode  Guide Star Processing  Compute/Check Target Quaternion  HGA Pointing  Generate Commands  Thrusters  Micro-Newton Thrusters  ST  HGA  Detect & Process ACS Faults ACS/ACE Software Functions (Detector)

6. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 6 ACS/ACE Software Functions (Hub)  Sensor Data Acquisition & Processing  CSS (8)  ST (2)  IRU (1)  Accelerometer (1)  Thrusters (4)  Micro-Newton Thrusters (12)  Beacons for MirrorSat (6)  Beacon for Detector (1)  Validate Ephemeris Update  Compute Solar Ephemeris  Compute Lunar Ephemeris  Compute Total Momentum  Estimate State Vector  Disturbance & Inertia Estimations  Adoptive Control & Formation Flying  ACE Safemode Processing  Collision Avoidance  Execute Science Mode Processing  Execute Maneuver Mode  Guide Star Processing  Compute/Check Target Quaternion  HGA Pointing  Generate Commands  Thrusters  Micro-Newton Thrusters  ST  HGA  Detect & Process ACS Faults (2 configurations, self & MirrorSats when attached)

7. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 7 ACS/ACE Software Functions (MirrorSat)  Sensor Data Acquisition & Processing  CSS (8)  ST (2)  IRU (1)  Swarm Sensor (1)  Thrusters (4)  Micro-Newton Thrusters (12)  Validate Ephemeris Update  Compute Solar Ephemeris  Compute Lunar Ephemeris  Compute Total Momentum  Estimate State Vector  Disturbance & Inertia Estimations  Adoptive Control & Formation Flying  ACE Safemode Processing  Collision Avoidance  Execute Science Mode Processing  Execute Maneuver Mode  Guide Star Processing  Compute/Check Target Quaternion  Generate Commands  Thrusters  Micro-Newton Thrusters  ST  Detect & Process ACS Faults

8. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 8 Instrument Software Functions Function  Mechanisms control  Exposure control  Read out CCD  Calibration  H-K data collection Detector (1)  yes MirrorSat (6)  yes  no  yes Hub (1)  yes

9. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 9 Typical Phase I Development Test Bed ACS/C&DH (Detector) Hybrid Dynamic Simulator Spacecraft External Data Bus (IP/Ethernet) Transponder Simulator Misc data simulator Development Workstation Serial Interface SI data simulator ACE (Detector) Ground System Workstations Development Workstation A similar configuration for Hub/MirrorSat not shown

10. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 10 Final Phase Development (System) Test Bed Detector Development String Hub External Data Bus Transponder Simulator MirrorSat Constellation Simulator (n-1) Hub/MirrorSat Development String Ground System Workstations Transponder Simulator MSat External Data Bus

11. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 11 Flight Software Cost Estimates Summary  ItemDetector ($k)Hub ($k)MirroSats ($k)  Mgt & SW Sys. Eng.06 (0,900)06 (0,900)06 (0,900)  C&DH Software15 (2,250)18 (2,700)20 (3,000)  ACS/ACE Software20 (3,000)25 (3,750)25 (3,750)  PSE Software04 (0,600)04 (0,600)09 (1,350)  Instrument Software04 (0,600)04 (0,600)09 (1,350)  Software Systems Test05 (0,750)07 (1,050)10 (1,500)  Formation Flying System Test02 (0,300)03 (0,450)07 (1,050)  I&T, H/W Spt. & Maint.08 (1,200)08 (1,200)12 (1,800)  Testbed Engineering02 (0,300)02 (0,300)05 (0,750)  Hardware & Software Tools (0,200)(0,200) (0,500)  Total Labor* & Materials66 (10,100)77 (11,750)103 (15,950)  Grand Total246 FTEs (37,800k) Assumed $150K/M-Y Breadboards & ETUs for C&DH, PSE & ACE, ACS HDS, GSE and Front-end simulator book-kept elsewhere

12. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 12 Flight Software Risk Assessment  WV IV&V Cost keep at project level.  Today/near-future flight CPU can handle the estimated processing  Flight IP/Ethernet technologies should be matured in 2010  New concepts required for software system-level testing due to nature of constellation  MirrorSat Constellation simulator in addition to traditional HDS  Phased testbed development environment ranging from single subsystem c/o to full flight data system string (over 30 sets of software system development)  Early data system component development required to support FSW development in all areas to mitigate risks  Early development and c/o of breadboards/ETUs will be required  Typical software risks apply  Good industry practices  Adequate test time  Adequate test resources  Adequate documentation

13. Final Version MAXIM-PF, May 13-17, 2002 Goddard Space Flight Center Flight Software Page 13 Flight Software Issues and Concerns  Several novel control concepts required to manage this particular constellation  No heritage in developing test strategy for this type of application  Multiple constellation configurations of mission phases add significant complexity to flight software and test strategy.  Further development of concept of failure detection & correction, and redundancy management is required.  Cost may be significantly differ from today estimates (recommend further development of the concept)  Procurement strategy will have a significant impact (# of sources)