Repeatability is not only a simulator property
A HIL workflow may use strong tools and still produce uncertainty. The same test can feel different when setup steps change, versions drift, operator notes are missing, or evidence is stored in different places.
Repeatability depends on the whole workflow.
What changes between runs
For one HIL workflow, inspect:
- Simulator and model versions.
- Device firmware and configuration.
- Test sequence or script versions.
- Stand wiring, fixtures, and calibration assumptions.
- Manual setup steps.
- Environment conditions that affect interpretation.
- Result collection and report generation.
If those items are not visible after the run, the team may have a repeatability problem even when the test itself executed correctly.
What a workflow map can reveal
A map separates the technical test from the surrounding operational steps. It shows which parts are deterministic, which parts rely on people, and which parts need better evidence capture.
That makes the next improvement smaller. Instead of debating a whole platform, the team can decide whether one setup step, one handoff, or one evidence gap is worth fixing first.
If the workflow sits inside an automotive safety context, use the ISO 26262 HIL traceability diagnostic as a safer next lens. It keeps the focus on evidence mapping and traceability gaps, not on claiming compliance.
Start with one run type
Do not try to map every HIL workflow at once. Pick one run type that creates recurring confusion and map it from setup to review. The result should show where repeatability is currently protected and where it depends on memory.
Quick self-check: HIL repeatability
Pick one HIL run type you would want to defend in a review. Answer honestly.
| Question | Yes | Partly | No |
|---|---|---|---|
| Is the simulator model version captured with each run? | |||
| Is the DUT firmware version recorded per run? | |||
| Are test script versions tracked? | |||
| Is stand wiring/calibration documented before the run? | |||
| Are manual operator steps recorded? | |||
| Can you reproduce a run from 6 months ago without asking the person who ran it? |
Count your “No” answers:
- 0-1 No: Your HIL repeatability is well managed. A diagnostic might still find automation savings, but the basics are in place.
- 2-3 No: There are specific gaps worth mapping. Use the diagnostic kit on this one run type – it takes 30-45 minutes and does not require sharing confidential data.
- 4+ No: Repeatability likely depends on specific people rather than a documented process. A workflow review can help decide which gap to close first, before a tool decision is on the table.
This checklist is a thinking tool. It does not certify anything – it helps you decide whether one run type is worth a closer look.
Understand why HIL test repeatability problems can come from workflow context.