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Published

traffic light

vr.tr.traffic-light · thing-q8004

Let an agent handle traffic lights by type, signal meaning, timing, accessibility and faults, with road rules by country.

Thing Registry Physical world and living systems PHY.OBJ
Bundle → Layer → Finding → QuestionsClassifiersWhat it isWhy it existsDistinguishing featuresWhat robots and AI may and may not doMoral aspectsOwnersLinks to other meta-modelsIdentity and identifiersDirect propertiesRecognitionCapabilities and actionsHazards and failure modesStandards and interfacesContext of useSources

Bundle → Layer → Finding → Questions Filled

4 bundles · 8 layers · 8 findings · 16 questions

Meaning What signals mean.

Colours

Red, amber, green.

Colours

Signal meaning.

  1. What does each signal mean in this country? provenance
  2. Is right turn on red allowed? boundary

Arrows

Filters.

Arrows

Arrow signals.

  1. What do arrow signals permit? definition
  2. Do pedestrians have priority? boundary
Operation Timing.

Timing

Cycles.

Timing

Timing.

  1. Is the signal fixed-time or adaptive? definition
  2. What is the cycle length? measurement

Pedestrians

Crossing time.

Pedestrians

Pedestrian timing.

  1. Is crossing time long enough for slower pedestrians? boundary
  2. Which standard walking speed is assumed? measurement
Accessibility Inclusive signals.

Audible and tactile

Signals for blind people.

Audible

Accessible signals.

  1. Does the crossing have audible or tactile signals? definition
  2. How can they be requested? action

Colour vision

Position cues.

Colour

Colour vision.

  1. Can people with colour vision deficiency read the signal by position? boundary
  2. Is the layout standard? provenance
Faults Failures.

Failure

What to do.

Failure

Signal failure.

  1. What are the rules when lights are out? provenance
  2. How should drivers proceed? action

Reporting

Road authority.

Reporting

Fault reporting.

  1. How can a fault be reported? action
  2. To which authority? provenance

Classifiers Filled

Family
Thing Registry
Category
Physical world and living systems
Entry kind
thing
Plane
PHY
Domain
PHY.OBJ
Other names and narrower kinds
Traffic lights in Korea, fixed-time traffic light, temporary traffic lights, traffic signals in Poland, pedestrian signal, flashing single‑lamp signal, speed sign, ramp meter, In-ground crossing light, traffic lights in Japan, solar traffic light

What it is Filled

A signalling device at road intersections, pedestrian crossings and other locations that controls traffic with coloured lights, usually red, amber and green, and pedestrian signals.

Why it exists Filled

Let an agent handle traffic lights by type, signal meaning, timing, accessibility and faults, with road rules by country.

Distinguishing features Filled

  • Controls traffic by coloured lights
  • Fixed-time or adaptive
  • Signal meanings vary by country
  • Accessible signals help blind pedestrians

What robots and AI may and may not do Filled

Must not

  • Change the timing or state of traffic lights without the road authority's authority.
  • Proceed against a red signal except when directed by police or an emergency procedure.
  • Interfere with signal priority systems for emergency or public transport vehicles.
  • Treat a dark or flashing signal as a green light.

Only with a human decision

  • Overriding signals during an emergency or an incident.
  • Changing pedestrian crossing timings.

May

  • Read a traffic light's state and obey it.
  • Report faulty, dark or obscured signals to the road authority.

Moral aspects Filled

  • Signal faults and tampering cause collisions that kill and injure people.
  • Signal timings shape safety and waiting time for pedestrians, the elderly and disabled people.

Who is affected

  • Drivers and riders
  • Pedestrians and cyclists
  • Emergency services

Owners Filled

Steward

The road or highway authority that installs and operates it.

Master systems

  • Road authority asset and traffic signal registers

Links to other meta-models Filled

parent

  • Q105449313 - registry parent class
  • Q1146001 - registry parent class
  • Q2354362 - registry parent class
  • Q7339568 - registry parent class

related

  • road equipment and physical sign - category
  • road traffic - use
  • intersection - place
  • road traffic rules - rules

What else AI and robots need to interact with it Filled

Identity and identifiers required Filled

  • Vercy registry: vr.tr.traffic-light
  • Wikidata: Q8004 (https://www.wikidata.org/wiki/Q8004)

Direct properties required Filled

  • Signal aperture diameter: mm - Measure the diameter of the visible illuminated aperture, distinguishing vehicle signals from pedestrian displays.
  • Luminous intensity: cd - Measure luminous intensity at specified viewing angles with calibrated photometric equipment.
  • Mounting height: m - Measure vertically from the road or footway surface to a stated reference point on the signal head.
  • Electrical power consumption: W - Measure electrical input power for the specified illuminated aspect and operating condition.

Recognition required Filled

  • Red, amber, green lamps
  • Arrow and pedestrian signals
  • Temporary portable lights at roadworks
  • Poles or gantries with red, amber and green lamps and pedestrian figures.

Capabilities and actions required Filled

  • obey signals
  • report faults to the road authority
  • plan signal timing
  • provide accessible pedestrian signals

Hazards and failure modes required Filled

  • Signal failures at busy junctions
  • Running red lights
  • Short pedestrian crossing times

Standards and interfaces required Filled

  • Vienna Convention on Road Signs and Signals
  • EN 12368 traffic control equipment
  • National traffic signal manuals such as MUTCD

Context of use required Filled

  • Controlling conflicting traffic flows safely.
  • fixed-time signals
  • actuated and adaptive signals
  • pedestrian and cycle signals
  • temporary traffic lights
  • flashing warning signals

Sources Filled

  1. Wikidata item Q8004: traffic light - identity and sense of the item
  2. Wikipedia: Traffic light - general description of the item

Open questions

  • Should signal types be separate entries?
  • How should country rules be linked?
  • How should fault reporting be localised?

Machine files

Card as JSON Specification Card backlog vercy.card/1

Provenance

thing registry research (pass 2) · unreviewed

Built from: models/things/publications/thing-q8004/spec.json