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

Figure 4-3. Number of hours of re-planning required per day during IOC.In addition, these same mission planners were on-call 24 hours a day, 7 days a week during both the IOC andscience phases of the mission, to support emergency changes in the SN and GN schedules, as well as on-orbitconditions which required middle-of-the-night load re-building.4.2.3.3 Flexibility Showcase: Timeline AutomationDuring the Calibration phase of the mission, MP designed and deployed a macro language for TCRs, buildingon our extensive experience with timeline design in the IOC and Science phases. The operations concept wassimple:• A Calibration baseline was created. This is a very simple, repeating structure where every week is thesame.• A TCR for each calibration activity was created – one per day. These TCRs were designed and discussedfor months prior to use.• The TCRs were “marked up” using a macro language developed by MP. These macros were also humanreadableand intuitive.• The macro TCR would be approved, and on the day of its use, it would be run through the processingsoftware which would produce a GREAS file which contained the timeline instructions necessary toimplement the TCR.• A MP would then incorporate this GREAS file into the baseline GREAS file and massage thecomponents into agreement. Some human work is still required, but hours of grunt work waseliminated, and human error removed!Gravity Probe B — Post Flight Analysis • Final Report March 2007 105