Stop burning engineering hours on tests a machine can run overnight

The building blocks depend on what is under test. For embedded products we build hardware-in-the-loop rigs: real firmware on real boards, surrounded by simulated sensors and loads, relay or SMU-switched fault injection, and power cycling under script control, so every firmware commit can face the full torture suite. For instrument-based testing we script the bench itself — SCPI over VISA to supplies, scopes, DMMs, and environmental chambers — turning a week of manual characterization into an overnight queue. Results land in a database with full configuration capture, and the suite runs from CI where that fits, so a failing test blocks a merge instead of surprising a customer.

Success is measured in cadence and confidence: regression coverage that runs on every build instead of every release, characterization matrices that grow because they are cheap now, and engineers reallocated from executing tests to designing better ones. The first time the overnight run catches a regression that manual spot-checking would have missed, the rig has typically justified itself.

Not every test deserves automation, and the first job is deciding which ones do. We rank candidates by how often they run, how long they take, how error-prone the manual version is, and how expensive the escapes have been, then start with the small set that pays back fastest — often a single regression suite or one characterization sweep. That first rig is deliberately modest, built on a pattern that can grow: instrument abstractions, a test definition format, and a results schema that will still make sense when the suite is ten times larger. Coverage expands from there, one procedure at a time.

An automated suite that never fails is a suite that is not testing anything; part of commissioning is proving the rig catches known-bad firmware and deliberately broken hardware. We also expect it to surface things nobody was looking for — an intermittent that only shows on the four-hundredth power cycle, a timing margin that was always thin — and those findings are treated as a first return on the investment rather than a distraction. Everything delivered — rig drawings, wiring, fixture CAD, test source, and results schema — is yours in editable form, structured so your engineers, not ours, are the ones extending it.