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distance

vr.tr.distance · thing-q126017

Let an agent state distances with their path, unit, method and uncertainty, and never mix straight-line, route and travel-time distances.

Thing Registry Cross-cutting context XCT.TME
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

Definition and path What distance is meant.

Path

Straight line, great circle or route.

Path type

The path along which distance is taken.

  1. Along which path is this distance measured? definition
  2. How different is it from the straight-line distance? measurement

Endpoints

The two points.

Endpoint definition

The points and their coordinates.

  1. Between which two points exactly? definition
  2. How precisely are those points located? measurement
Measurement How it was obtained.

Method

Survey, GNSS, odometer, calculation.

Measurement method

The method and instrument.

  1. How was this distance measured or computed? provenance
  2. What is its uncertainty? measurement

Reference system

Datum and projection.

Reference frame

The datum and projection used.

  1. Which datum and projection were used? provenance
  2. How much distortion does the projection introduce? measurement
Units Units and conversion.

Unit

The unit stated.

Unit stated

The unit and its definition.

  1. In which unit is this distance given? definition
  2. Could the unit be misread? boundary

Conversion

Converting units.

Conversion factors

Exact conversion factors.

  1. Which exact factor converts this unit to metres? measurement
  2. What rounding was applied? measurement
Use Distances in decisions.

Application

Where the distance is used.

Use context

The decision the distance feeds.

  1. What decision does this distance feed? definition
  2. Would a travel time be more appropriate? boundary

Safety margins

Distances as limits.

Margin rules

Required minimum distances.

  1. Is a minimum distance required here, and by which rule? provenance
  2. How is compliance measured? measurement

Classifiers Filled

Family
Thing Registry
Category
Cross-cutting context
Entry kind
thing
Plane
XCT
Domain
XCT.TME
Other names and narrower kinds
medium track gauge railway, minimum track gauge, 1429 mm track gauge, 1050 mm track gauge, 1200 mm track gauge, 1100 mm track gauge, 1106 mm track gauge, four-foot gauge, track gauge, track gauge in Spain, Ten and a quarter inch gauge, pupillary distance

What it is Filled

The length of the straight line connecting two points in a measurable or observable physical space, expressed in units of length.

Why it exists Filled

Let an agent state distances with their path, unit, method and uncertainty, and never mix straight-line, route and travel-time distances.

Distinguishing features Filled

  • It measures straight-line length between two points.
  • It is distinct from displacement, which has direction.
  • It is distinct from travel time, which depends on speed.
  • It always needs a unit and ideally a stated measurement method.

What robots and AI may and may not do Filled

Must not

  • Mix straight-line, route and travel-time distances in one answer without saying so.
  • Report a distance in the wrong unit where navigation, aviation or dosing depends on it.
  • Use distance calculations to track a person's movements without consent.

Only with a human decision

  • Relying on a computed distance for safety-critical clearances.

May

  • Measure or compute distances, stating the path, unit and method.
  • Convert distances between units for its user.

Moral aspects Filled

  • Distance errors in navigation and engineering can put lives at risk.
  • Distance from services decides access to care and help in an emergency.

Who is affected

  • Travellers and navigators
  • People relying on emergency response

Owners Filled

Steward

Nobody owns it; national metrology institutes maintain the units of length.

Links to other meta-models Filled

parent

  • Q107715 - registry parent class
  • Q181175 - registry parent class
  • Q30241068 - registry parent class

related

  • length - a physical quantity measured in metres
  • displacement - displacement is a vector
  • transport and navigation - routes, fares and plans depend on it
  • track gauge - the distance between rails

What else AI and robots need to interact with it Filled

Identity and identifiers required Filled

  • Vercy registry: vr.tr.distance
  • Wikidata: Q126017 (https://www.wikidata.org/wiki/Q126017)
  • SI unit: metre, symbol m base unit of length

Direct properties not applicable Not applicable

  • unit: metre (SI) m - mile 1609.344 m, nautical mile 1852 m

Plane XCT: no invented physical properties.

Recognition optional Filled

  • A number with a length unit: m, km, mi, nmi, ft
  • Road signs and maps state route or straight-line distances
  • Track gauge, a distance between rails, is one specialised distance
  • Not a thing to look at; seen on maps, signs and instruments as a number with a unit.

Capabilities and actions required Filled

  • measure it, by survey, GNSS, laser or odometer
  • compute it, from coordinates or a network
  • convert it between units
  • use it, for routing, pricing and planning

Hazards and failure modes required Filled

  • Unit confusion, such as miles for kilometres or feet for metres
  • Mixing straight-line and route distances
  • Projection errors when measuring on flat maps

Standards and interfaces required Filled

  • International System of Units (SI)
  • ISO 80000-3 space and time quantities
  • WGS 84 for geodetic distances

Context of use required Filled

  • Measuring separation, for navigation, planning, engineering and science.
  • Euclidean, great-circle, geodesic, route or network distance
  • specialised distances such as track gauge and wheelbase
  • abstract distances in mathematics, such as metric distances

Sources Filled

  1. Wikidata item Q126017: distance - identity and sense of the item
  2. Wikipedia: Distance - general description of the item

Open questions

  • Should route distance and straight-line distance be separate entries?
  • How should uncertainty in measured distances be recorded?
  • Should specialised distances such as track gauge be children of this entry?

Machine files

Card as JSON Specification Card backlog vercy.card/1

Provenance

thing registry research (pass 2) · unreviewed

Built from: models/things/publications/thing-q126017/spec.json