1. Exploring the whole machine

Arthur C. Clarke’s Rendezvous with Rama returns as the recalled work because the integrated system test is another exploration of a sealed machine with instruments and stopping rules. The desktop is not alien, but it is complex enough that its behavior under combined loads can only be discovered by running it. The pass criteria must separate a healthy platform from one that is merely surviving by accident.

This entry defines success and failure for the integrated system test.

2. Minimum success

The integrated system test passes if:

  • The platform maintains all critical functions through every nominal and peak-load case.
  • Power, thermal, compute, storage, and network metrics remain within their design budgets.
  • A cell swap under load completes without data loss or service interruption beyond the policy limit.
  • Ground-link loss does not cause unrecoverable state or data loss.
  • No protection circuit false-trips during any case.
  • The platform returns to a stable state after each transient.

This minimum says the desktop can operate as an integrated platform under expected conditions.

3. Full success

A stronger result would add:

  • Margin remains after peak load; the platform is not operating at its limit.
  • Transient responses are smooth and predictable.
  • Autonomous responses, such as thermal shedding or workload migration, occur only when intended.
  • The platform recovers from combined stress without manual intervention.
  • Test data supports prediction of on-orbit behavior.

This stronger result supports a claim of flight readiness, not just functional integration.

4. Failure modes

The test fails if any of the following occur:

  • A critical function is lost during a nominal or peak-load case.
  • A protection circuit trips unexpectedly.
  • A thermal runaway or thermal oscillation occurs.
  • A power bus undervoltage or overvoltage exceeds tolerance.
  • A cell drops out of the federation and is not recovered.
  • A cell swap causes data loss or corruption.
  • The platform does not return to a stable state after a transient.

Each failure mode points to a cross-domain fix: control tuning, load shedding, sequencing, or additional margin.

5. What this changes

  • The integrated system test has clear pass and fail criteria.
  • The criteria separate subsystem survival from integrated platform health.
  • The next entry will close the integrated system test arc.