spatial.owm

Open World Model

A live model of a place, built from claims.

The Open World Model is how many independent parties share one model of a real place without sharing a database. Entities carry how they are known: observed, declared, authored, or derived. Relationships are claims: somebody asserts them, on some basis, at some time. Claims from different parties coexist, and when an assertion ends, it ends with a reason.

Replaying a recorded session. The world is simulated (Eclipse SUMO); every claim is a real record from a live SpatialDDS bus.

simulated world · recorded claims

Claim record · one trace per edge, high while asserted

claims hidden: this is only the simulated street
observed declared derived authored (the map) line of sight, blocked ends: no longer holds ends: asserter stopped
A bus blocks a car's view of a pedestrian; a roadside sensor asserts what it sees and the car brakes on the claim. A rail gate declares its own future and traffic queues before anything moves. The world is simulated; every claim is a real record from a live SpatialDDS bus, replayed here. Flip the toggle to see the same scene without the model.

What a claim is

A claim names its subject, predicate, and object, who asserts it, on what basis, and when it holds. Spatial predicates cite GeoSPARQL. Two asserters can hold claims about the same proposition and neither wins; a consumer filters by asserter and basis and builds its own view. Identity across publishers works the same way: same-as is a claim, revisable and retirable, never a global merge. Assertion time and world time are kept apart, so a retirement can say whether the relationship ended or the asserter withdrew.

Where it stands

spatial.owm 0.1 ships as a provisional module of SpatialDDS 1.8, stamped October 2026. Three independent implementations run it in three roles: a reference venue with a browser client, a ROS 2 library on PyPI, and a sidecar publishing Intel SceneScape analytics as typed records. The 0.2 design round covers relationships and identity as claims. Read the proposal and the worked example.

If you keep an object model

An object model describes what one consumer holds in memory. OWM describes how many parties feed it over a network. The relationship is the one between the DOM and HTTP. Keep your object model as the consumer view, and let claims carry the interchange: who asserts what, on what basis, when, and how disagreement travels.

Try it

A public endpoint serves discovery and content at demo.spatialdds.org, with the full API at /.well-known/spatialdds/openapi.html. Publishing needs a token; contact Open AR Cloud. To run a venue of your own, install the Python package and start the gateway:

pip install "spatialdds[server]"
python -m spatialdds.serve --demo --authority registry.mytown.example

Replace registry.mytown.example with the DNS name your venue answers as. --demo seeds a small sample scene; drop it for an empty registry of your own. The registry mints a publishing token and prints it at startup.

Carried by SpatialDDS

OWM rides SpatialDDS, an open protocol for discovering and sharing spatial data. Spec, registry, and conformance suite at spatialdds.org.