GP-B Post-Flight Analysis—Final Report - Gravity Probe B - Stanford ...

packages, one for each Ping load and one for each Pong load, were several hundred pages in length, andcontained every MP product associated with that load, including the actual instructions (in humanreadablecode form) sent to the spacecraft.10. Once the load packages are approved and signed off by all the sub-system engineers and missionmanagers, the loads could be sent to the Real-time Operations team in the MOC. Mission Planningwould deploy the load products to both PODs (computer clusters capable of commanding thespacecraft) in the MOC, and would also deploy the final products to the web site for common availabilityto the entire mission.11. Finally, an abbreviated load package would be produced containing high-level products. This smallpackage would be photocopied and made available as the Ping and Pong loads were executing, so thatanyone on-site could easily determine what the spacecraft’s timeline and objectives were for the day. As acapstone to the day’s events, a thematic and clever cartoon would be harvested from a book or theinternet, and placed on the load package’s cover sheet to provide much-needed levity.12. Mission Planning was scheduled to leave for the day at 5pm.In the Science Phase of the mission, things were planned to get a lot simpler – with only a few loads per week.And in the Calibration phase, we would have one load per day.4.2.1.2 Success CriteriaOur success depends on three critical factors: (1) efficiency in the face of complex requirements, (2) flexibility ina dynamic environment, and (3) error-free results. Furthermore, the measure of our success is the quality of ourtwo sets of products – the Timeline and the Schedule – which closely interlock and co-evolve throughout theircreation on a daily basis. Mission Planners must:• Coordinate all the essential input from mission researchers, spacecraft engineers, and program managers– even as situations change from morning to night• Operate a rigorous set of quality assurance processes – to verify that the instructions received areprecisely implemented as intended• Operate a complex set of support software which facilitates the creation of timely, correct timelines andschedules – to meet the dynamic needs of spacecraft operations• Deliver its output into production: the timeline must be delivered to the spacecraft, and thecommunications schedule must be synchronized between the Stanford Mission Operations Center(“MOC”) and the NASA communications elements around the world4.2.1.3 Coordination: the Primary ChallengeMission Planning drives the development of the timeline and the schedule through its contacts with all theoperations, engineering, management, and NASA elements. The coordination required to develop a coherentproduct set – a spacecraft timeline and schedule – is extensive. The primary challenge of Mission Planning is tocapture, coordinate and properly understand all the various inputs from these sources.4.2.1.4 Mission Planning in a University SettingOf special significance is Gravity Probe-B’s implementation in a university setting. The Mission Planning teamcomprised a core group of two professional Mission Planners, supplemented by students. The coreprofessionals were subject matter experts in the timeline, schedule, and software tools, while the studentsmaintained expertise in niches and specific functions.100 March 2007 Chapter 4 — GP-B On Orbit