“Modeling the MER Mission”

1. “Modeling the MER Mission” Chin Seah NASA Ames Research Center

2. Outline • Mars Exploration Rover Mission • Mission Operations Modeling • MER Brahms Model • Brahms Model Affecting Design of Mission Operations • Predictive Model of Mission Operations • Lessons Learned Agent-Based Modeling & Simulation of Organizations and Work Practice

3. Mar Exploration Rover Mission“Find Past Existence of Water” Mars Exploration Rovers (MER) Spirit (MER-A) at Gusev Crater Reached Mars on Jan 4, ‘04 Opportunity (MER-B) at Meridiani Planum Reached Mars on Jan 25, ‘04 90 day mission which was extended. Science Payloads Panoramic Camera: Providing the geologic context Rock Abrasion Tool Grinding Outside of Rocks Mössbauer Spectrometer Identifying Iron-Bearing Minerals Miniature Thermal Emission Spectrometer Identifying Minerals at the Site Agent-Based Modeling & Simulation of Organizations and Work Practice

4. What is Mission Operations? “The control of one or more information gathering devices on board a vehicle in space and the associated operation of the vehicle systems in order to support information gathering.” Wall, S. & K. Ledbetter, ’91 Design of Mission Operations for Remote Sensing (Magellan Mission to Venus) Agent-Based Modeling & Simulation of Organizations and Work Practice

5. Why Work Practice Modeling for Mission Operations? • New designs for • Facilities • Organization • Processes • Complex work system • Scientists and Engineers • 24*7 • Multiple Time Zones • Data Systems (new & legacy) • Design close to implementation stage • Trial and error of design during Operations Readiness Tests Agent-Based Modeling & Simulation of Organizations and Work Practice

6. Where did data for model come from? • JPL’s Tactical Timeline in Excel spreadsheets, design specifications, software documentation, etc. • Participated in Mission Design Team’s design sessions • Interviewed people that were part of MER mission operations. • Observed JPL’s Operational Readiness Tests. Agent-Based Modeling & Simulation of Organizations and Work Practice

7. What to model? Nominal Surface Tactical Timeline • Organizational Structures and Roles • Operational procedures for roles • Engineering and Science decision making and planning • Rover on Mars • Receive commands from Earth (Uplink) • Command execution • Science Payload/Instrument • Capture of Science data • Send data back to Earth (Downlink) • Flow of Mission data • From Downlink to Uplink to Downlink of science and engineering data • Creation, flow and use of intermediate data • Communication between people, and between people and systems • Uplink rover command generation Agent-Based Modeling & Simulation of Organizations and Work Practice

8. MER Organization Mission Operations at JPL • 50 Science Team Members • 30 Engineering Team Members • Two Rover Teams (MER A & B) • 25 STM & 15 ETM per Rover Team • Two Shifts per Martian Day/Sol • Shift handovers • 4 floors within building • 90-Sol Minimal Mission Duration • Jan 2004 - Mar 2004 • MER A & B Operations overlap • Different Time Zones (2 on Mars, PDT at JPL) Agent-Based Modeling & Simulation of Organizations and Work Practice

9. MER Organization Model Agent-Based Modeling & Simulation of Organizations and Work Practice

10. RSVP SAP SAP SAP RSVP RSVP SAP CE SAP SAP RSVP MAPGEN MAPGEN Scientist Scientist Scientist SOWG Chair SOWG Chair TAP TAP Engineer PUL SIE PUL PUL RP PUL Uplink Tools Process Flow (Similar to traditional “Order Processing”) Plan Plan Plan Plan Plan Plan Plan Plan Plan Plan Plan Plan Plan Agent-Based Modeling & Simulation of Organizations and Work Practice

11. MER Information Model Agent-Based Modeling & Simulation of Organizations and Work Practice

12. Clock, Schedule and Agents CIP Clock Object Match Timeline with Mars time Reads Mars time Mars Clock Object Timeline Object Broadcasts time when match Timeline Activity happens within Timeline Contains timeline activities Is timeline over? Start next task? Do I start my shift? Contains mission operations activities Reads Associated Schedule Schedule Object Mission Operations Activity Conceptual Object Schedule Group Agent Agent-Based Modeling & Simulation of Organizations and Work Practice

13. MER Clock Model Agent-Based Modeling & Simulation of Organizations and Work Practice

14. Simulation of MER Clock Match Timeline Agent-Based Modeling & Simulation of Organizations and Work Practice

15. Issues of Modeling a Mission Operations • Actual Work Practice was different from design • We know this from our theory of work practice • How useful is model in design? • Unable to predict workflow failure • Round-Trip data tracking issue not identified • This could have been identified and solved in model design but … Much detail about mission data and systems needed Agent-Based Modeling & Simulation of Organizations and Work Practice

16. How Useful is Model in Design? • Synchronizing Communications of Key Personnel • People could not verbally communicate information because they needed to be in different places at the same time for meetings • People’s work hours were too long • A shift was about 8 to 10 martian hours Agent-Based Modeling & Simulation of Organizations and Work Practice

17. Other Uses of MER Brahms Model • Procedures for Mission Operations Personnel • Assist in Mission Operations Planning. • Creation of huge paper poster • Analysis of Mission Operations • Mars-based time versus Earth time (24 x 7 & 8 hours) • Simulation Visualization • Timeline view of information on Rover Activity Plan • Communication networks creation and growth Agent-Based Modeling & Simulation of Organizations and Work Practice

18. Constraint Editor MAPGEN SAP MAPGEN SOWG Chair SOWG Chair Tactical Activity Planner Tactical Activity Planner Predicting Workflow Failure:SAP and MAPGEN Scenario Without Sequence or Timing Constraints Plan SAP User Interface Plan With Sequence and Timing Constraints Interface ≠ Specification Agent-Based Modeling & Simulation of Organizations and Work Practice

19. What have we learned? How to model Mission Operations Systems Level of detail to model More narrow/deep or more broad/shallow Use of BRAHMS? • Representation • + Mars time vs. Earth time • + Multiple MER teams • + Systems • + Information flow • + Plans and schedules • Usefulness for mission designers • - Not easy to retrieve information • - Not easy to change model • - Difficult to model things • - Difficult to determine needed level • - Difficult what-if scenarios Agent-Based Modeling & Simulation of Organizations and Work Practice