Coverage & ontology · the trust boundary

Clear, degraded, or not observable are different answers.

Silence is only meaningful when the system can see. VESU makes coverage state part of the product output. The TMC should not have to infer monitoring loss from a missing alert.

01 · The three coverage states

One status. Always known. Always reported.

OK
cam_l2 · 14:33:05
Monitored & clear

Health checks pass. Stage 1 returning structured frames on cadence. Detection runs normally.

Green dot · confidence reported.
DEGRADED
cam_l2 · 14:33:05
Coverage degraded

Glare, blur, rain, fog, low light. Signal is degraded but not gone. Operator sees a yellow dot — not a green one.

Detection gated; advisory only. Nothing silently suppressed.
GAP
cam_l2 · 14:33:05
Coverage gap

Frozen feed, mis-aimed view, total obstruction. The coverage gap is the event.

Red dot · published as a P0 coverage event.
02 · Camera-health events

Camera health is not a DevOps metric. It is a TMC-relevant event.

If the camera is frozen, dark, blocked, pointed away from the road, or sitting in a PTZ transition, the TMC has lost situational awareness for that view.

Frozen feed
Darkness / underexposure
Overexposure
Blur
Obstruction (debris, ice, smoke on lens)
PTZ motion
View mismatch / drift
Visibility degraded
03 · Incident families

Grouped by intent, labelled by maturity.

Not every class is equally production-ready. The ontology is honest about which classes ship today, which are advisory, which are being evaluated, and which are designed-for-later.

production
advisory
evaluating
designed-for
open-set
Safety incidents
8 classes
Stopped vehicle production Debris in lane production Pedestrian in lane production Emergency vehicle presence production Work-zone activity advisory Smoke or fire cue advisory Wrong-way driver evaluating Collision aftermath evaluating
Environment & roadway
5 classes
Heavy rain / fog advisory Glare / dazzle advisory Darkness onset advisory Ponding / standing water evaluating Snow / ice on road designed-for
Camera & coverage
5 classes
Camera frozen production Camera misaligned production View obstructed production Coverage degraded production PTZ in motion production
Open-set
1 class
Unknown hazard open-set
04 · How coverage affects publication

Coverage state changes the decision.

A candidate from a degraded camera is not the same as a candidate from a healthy one. The publication gate uses both — and the operator sees the difference.

CANDIDATE Stage 2 → Stage 3 PUBLICATION GATE class · coverage · maturity PUBLISHED healthy + production class → ATMS ADVISORY degraded camera or advisory class SUPPRESSED coverage gap · or below gate COVERAGE EVENT gap reported as its own event

The boundaries of the system are part of the product.

If you would like to walk through how a specific class is currently scoped — production, advisory, evaluating — we are happy to do that with your traffic operations team.