# Presentation: 662023

## Micro-Arcsecond Imaging Mission, Pathfinder (MAXIM-PF)

**May 13-17, 2002**

**Micro-Arcsecond Imaging Mission, Pathfinder (MAXIM-PF)**

**Flight Software**

## 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

**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**

## 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.**

## 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**
**yes**
**no**
**yes**
**no**
**no**
**yes**
**yes**
**yes**
**yes**
**yes**
**no**
**yes**

_**Detector (1)**_
**yes (from GN) **
**yes **
**yes**
**yes**
**yes**
**yes**
**yes**
**yes**
**yes****	**
**yes**
**yes**
**yes**
**yes**
**no**

_**MirrorSat (6)**_
**yes (from Hub) **
**yes**
**yes**
**no**
**yes**
**no**
**no**
**yes**
**yes**
**yes**
**yes**
**yes**
**no**
**yes**

## 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

- 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)**

## 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

**(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)**

## 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

**(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 **

## Instrument Software Functions

_**Function**_
**Mechanisms control**
**Exposure control**
**Read out CCD**
**Calibration**
**H-K data collection**

_**Detector (1)**_
**yes**
**yes**
**yes**
**yes**
**yes**

_**MirrorSat (6)**_
**yes**
**no**
**no**
**yes**
**yes**

_**Hub (1)**_
**yes**
**yes**
**yes**
**yes**
**yes**

##  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

##  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**

## Flight Software Cost Estimates Summary

_**Item**_**	****	**_**Detector ($k)**_**	**_**Hub ($k)**_**	**_**MirroSats ($k)**_**	**
**Mgt & SW Sys. Eng.****	****06 (0,900)****	****06 (0,900)****	****06 (0,900)**
**C&DH Software****	****15 (2,250)****	****18 (2,700)****	****20 (3,000)**
**ACS/ACE Software****	****20 (3,000)****	****25 (3,750)****	****25 (3,750)**
**PSE Software****	****04 (0,600)****	****04 (0,600)****	****09 (1,350)**
**Instrument Software****	****04 (0,600)****	****04 (0,600)****	****09 (1,350)**
**Software Systems Test****	****05 (0,750)****	****07 (1,050)****	****10 (1,500)**
**Formation Flying System Test****	****02 (0,300)****	****03 (0,450)****	****07 (1,050)**
**I&T, H/W Spt. & Maint.****	****08 (1,200)****	****08 (1,200)****	****12 (1,800)**
**Testbed Engineering****	****02 (0,300)****	****02 (0,300)****	****05 (0,750)**
**Hardware & Software Tools ****	****    (0,200)****	****(0,200)****	****    (0,500)****	**
**Total Labor********* & Materials****	****66 (10,100)****	****77 (11,750)****	****103 (15,950)**
**Grand Total****	****246 FTEs (37,800k)**
- Assumed $150K/M-Y
- Breadboards & ETUs for C&DH, PSE & ACE, ACS HDS, GSE and Front-end simulator book-kept elsewhere

##  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

##  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)