1. Inside a machine that cannot be opened carelessly
Arthur C. Clarke’s Rendezvous with Rama returns as the recalled work because the explorers spend the book moving through a sealed machine where every action has mechanical consequences. A cell swap on the desktop is similar: the mechanism must move precisely, the rack must tolerate the motion, and the rest of the platform must keep working while the operation is in progress.
This entry defines the autonomous swap test matrix for the desktop.
2. Test setup
The test uses a representative rack with at least four cells and one spare cell. One cell is designated as the swap target. The swap mechanism can be a robotic arm, a guided carriage, or any other flight-representative approach. The platform is powered and communicating during the test.
3. The test matrix
| Case | Event | Starting state | Expected outcome |
|---|---|---|---|
| 1 | Nominal swap | Target cell healthy, platform stable | Cell is extracted, spare inserted, platform resumes full operation. |
| 2 | Swap after simulated failure | Target cell powered off or degraded | Same as nominal; platform detects unavailable cell and waits for replacement. |
| 3 | Swap with partial rack load | Some cells already inactive | Remaining cells maintain operation and network during the swap. |
| 4 | Swap abort | Mechanism detects obstruction or over-force | Operation stops, original cell remains safely seated, alarm raised. |
| 5 | Reinsert original cell | Spare unavailable, original cell reinstalled | Original cell is re-admitted and workloads resume. |
| 6 | Multiple sequential swaps | Two or more cells swapped in series | Each swap completes cleanly; platform state remains consistent. |
| 7 | Swap under thermal-vacuum conditions | Test in TVAC or equivalent | Mechanical tolerances and connector mate behavior remain within spec. |
Each case is run at least twice: once under ground-controlled operation and once under autonomous control if available.
4. What is measured
For each case the test records:
- Force and torque profiles during release, extraction, insertion, and latch.
- Alignment error at mate.
- Electrical continuity of power and data contacts.
- Time from start of swap to full network admission.
- Whether workloads are correctly reassigned.
- Whether the platform maintained critical functions throughout.
5. What this changes
- The autonomous swap test has a concrete matrix.
- The matrix links back to the autonomous cell-swapping, connector reliability, and network reconfiguration arcs.
- The next entry will define pass and fail criteria.