1. The wondering log
John Scalzi’s Old Man’s War returns one last time for this arc because the desktop’s ADCS, like the novel’s soldiers, must adapt to a new body and learn to trust its senses. Entries 841 through 843 wondered about pointing modes, sensor fusion, and momentum management. This entry closes the arc.
2. What was decided
The ADCS wondering arc produced three aligned concerns:
- Pointing modes. Start with nadir, sun, and safe modes. Add modes only when the mission genuinely needs them.
- Sensor fusion. Autonomous fault detection with ground notification, and autonomous recovery limited to safe-mode cases. Test the filter with injected sensor faults.
- Momentum and disturbances. Size wheels and magnetorquers for routine LEO disturbances; use thrusters as backup desaturation. Treat propulsion burns as ADCS events.
3. The decided posture
The Resident will:
- Derive the pointing-mode list from mission needs rather than capability.
- Design the estimator to degrade gracefully when sensors fail or disagree.
- Size the momentum-management system for predicted disturbances plus margin.
- Model propulsion burns with thrust-vector/center-of-mass coupling.
- Include sensor-fault and momentum-saturation tests in the qualification campaign.
4. What this changes
- The ADCS wondering arc is complete.
- The desktop’s ADCS concept now includes operational behavior and failure response.
- The Resident is ready to define the test campaign that proves the ADCS works.