PhysicalVehicle¶

Status¶

Normative

Definition¶

A PhysicalVehicle represents an individual physical means of transport used to provide transport services.

It represents the transport asset itself, independently of the journeys, routes, operating days, or services to which it is assigned.

A PhysicalVehicle may be assigned to different transport operations during its operational lifetime.

Identity¶

The semantic identity of a PhysicalVehicle is established by the identity of the physical transport asset itself.

A PhysicalVehicle remains the same semantic instance when:

it is assigned to a different journey;
it operates on a different route;
it is assigned to a different operating day;
its operational state changes;
its public-facing label or fleet number changes; or
its recorded properties are updated.

A change of identifier in a source system does not by itself establish that a different PhysicalVehicle exists.

A replacement vehicle, even when assigned to the same journey or operational duty, represents a distinct PhysicalVehicle.

The construction of implementation identifiers for PhysicalVehicle instances is defined by the relevant mapping specification and is not prescribed by this semantic model.

Motivation¶

Transport information systems frequently use the term vehicle for different concepts, including:

a physical transport asset;
a type or classification of vehicle;
a scheduled vehicle operation;
a real-time vehicle observation; and
a vehicle assigned to a particular journey.

These concepts shall remain semantically distinct.

PhysicalVehicle represents only the individual physical transport asset.

Separating the vehicle from the journey allows the same vehicle to be assigned to multiple operations without changing its semantic identity.

Characteristics¶

A PhysicalVehicle:

represents one individual physical transport asset;
may be classified by one or more vehicle characteristics;
may be assigned to different journeys over time;
may carry equipment and accessibility facilities;
exists independently of any particular route or timetable;
exists independently of real-time observations; and
is distinct from a vehicle type or vehicle model.

Relationships¶

Vehicle Type¶

A PhysicalVehicle may be classified by a vehicle type.

The vehicle type describes common characteristics shared by multiple vehicles, such as transport mode, capacity, configuration, or operational capabilities.

The vehicle type is not the physical vehicle itself.

DatedVehicleJourney¶

A PhysicalVehicle may be assigned to operate one or more DatedVehicleJourneys over time.

A DatedVehicleJourney may exist before a PhysicalVehicle has been assigned to it.

Vehicle assignment does not determine the semantic identity of either the PhysicalVehicle or the DatedVehicleJourney.

MonitoredVehicleJourney¶

A PhysicalVehicle may operate a MonitoredVehicleJourney.

A MonitoredVehicleJourney describes the monitored operational execution of a journey and does not replace the identity of the PhysicalVehicle.

Operator¶

A PhysicalVehicle may be owned, managed, or operated by an organisation.

Ownership, management, and operational responsibility are separate semantic relationships and shall not be treated as equivalent unless a source specification explicitly establishes that equivalence.

Typical Properties¶

Typical semantic properties include:

identifier
label
fleetNumber
registrationNumber
vehicleType
transportMode
operator
capacity
accessibilityFeatures
onboardEquipment
operationalStatus

The presence of a typical property does not make it mandatory.

This semantic model does not prescribe implementation-specific property names, value encodings, or data structures.

Origin¶

This semantic concept is harmonized primarily from:

Transmodel — VEHICLE
Transmodel — VEHICLE TYPE
GTFS-Realtime — VehicleDescriptor
Schema.org — Vehicle

Transmodel defines VEHICLE as a physical public transport vehicle used for short-term operational planning and daily assignment.

SCRA Schema uses the name PhysicalVehicle to make the physical nature of the concept explicit and to distinguish it from vehicle journeys, vehicle types, and source-specific uses of the term Vehicle.

This naming clarification does not change the fundamental meaning of the Transmodel concept.

Mapping Guidance¶

Typical mappings include:

Source	Semantic Mapping
Transmodel `VEHICLE`	PhysicalVehicle
GTFS-Realtime `VehicleDescriptor.id`	Source identifier for PhysicalVehicle
GTFS-Realtime `VehicleDescriptor.label`	PhysicalVehicle label
GTFS-Realtime `VehicleDescriptor.license_plate`	PhysicalVehicle registration number

A source identifier shall not automatically be assumed to provide globally stable semantic identity.

Where a data source does not provide a persistent identifier for the physical asset, the mapping shall document the scope and limitations of the resulting identity.

This section is informative and does not form part of the normative semantic definition.