Building Definition Language

A coordinate system declaration shall define:

Coordinate System ID;

coordinate-system type;

parent coordinate system;

origin;

axis directions;

handedness;

angular convention;

length unit;

orientation;

transformation to its parent;

accuracy or uncertainty;

applicable configuration status.

BDL shall support:

geodetic site coordinates;

surveyed project coordinates;

building-local coordinates;

structural-grid coordinates;

level-local coordinates;

zone and room coordinates;

assembly coordinates;

Component coordinates;

Cartridge coordinates;

Interface coordinates;

robotic task coordinates.

System05 Cartesian coordinate systems shall use a right-handed convention unless a declared external source requires another convention.

A building-local system may be declared as:

coordinate_system Building_CS {

id: "s05:coordinate-system:building-001";

type: cartesian_3d;

parent: @Site_CS;

origin: [125.400 m, 82.750 m, 102.350 m];

x_axis: [1, 0, 0];

y_axis: [0, 1, 0];

z_axis: [0, 0, 1];

handedness: right;

length_unit: mm;

}

Every spatial Entity shall either declare its coordinate system or inherit it through an explicit containment relationship.

Coordinate inheritance shall not be assumed across imported models unless the transformation is known and validated.

Geodetic coordinate systems shall reference a recognized coordinate-reference identifier or a complete definition sufficient for transformation.

The BIOS, Digital Twin, survey model, and robotic model shall maintain traceable transformations to the authoritative building coordinate system.

A coordinate system with unresolved origin, orientation, unit, or handedness shall not be used for manufacturing, robotic installation, or safety-critical geometric validation.