SPC trends and capability

Trends, under VoraControl at /control/trends, builds SPC directly on the capture stream. Because measurements are recorded against a released control plan characteristic, every sample already carries the part, revision, operation, specification limits and gauge. Charts and Cp/Cpk are computed from those same records, per characteristic, so capability is always current and always tied to the limits it was measured against.

The overview dashboard

The dashboard summarizes measured characteristics, out-of-spec samples, possible drift signals, capability-ready characteristics and those without enough data yet. You can filter by signal (needs attention, out-of-spec, possible drift, near tolerance limit, low data, or no current signal), by capability readiness, and by date range, including sample-count windows such as the last 100, 500 or 1000 samples. A process health view groups the picture by customer and part.

Signals to review

A signal in Trends is a prompt to look, not a verdict. Possible drift means recent readings show a movement pattern worth reviewing; near tolerance limit means readings are running close to a spec limit. Out-of-spec is the hard signal: the result already failed its limits, and it is flagged instantly and handed to Resolve so the response is recorded alongside the measurement.

Cp and Cpk

The characteristic detail view shows Cp and Cpk once the data supports them. Capability stays hidden until there are enough comparable numeric samples, both spec limits, consistent tolerance details and usable variation. The minimum sample count is set in System under SPC settings; values below 30 are not allowed, so a capability figure never appears on thin evidence.

The same records answer the auditor

Because SPC is computed from capture records rather than a separate spreadsheet, there is no capability study that goes stale. The same records power the SPC and capability evidence in VoraAudit, ready to review or print when the auditor asks.