Overview
ISO 10303-112:2006 is part of the ISO 10303 (STEP) family and defines an Integrated Application Resource for exchanging procedurally represented 2D CAD models. The standard specifies how procedural representations-expressed as sequences of modelling commands-are represented so sketches and profiles (2D geometry created by operations) can be reliably exchanged between systems. The document includes EXPRESS schemas, function definitions and examples to support computer-interpretable transfer of procedural sketch data.
Key topics and requirements
- Procedural sketch model: Represents 2D sketches as ordered modelling commands (construction history) rather than only final geometry.
- Standardized command set: Defines many sketch operations such as:
- line and polyline creation (create_line_segment*, create_polyline)
- circle and arc creation (create_circle*, create_circular_arc*)
- ellipse, spline, parabolic arc, fillet, chamfer
- pattern and transform operations (translate, rotate, mirror, scale, pattern_rectangular, pattern_circular)
- Explicit constraints and history: Support for representing construction history and explicit geometric constraints within a sketch.
- Entity and function definitions: Includes procedural_sketch entity definitions, function definitions (distance_between_cartesian_points, midpoint, etc.), and type definitions used by commands.
- Machine-readable artifacts: Contains EXPRESS-G diagrams, computer-interpretable listings, and normative annexes for entity short names and information object registration.
- Normative and informative content: Normative references and annexes (A, B) and informative examples (Annex E) to illustrate intended usage.
Applications and practical value
- CAD interoperability: Exchange of sketches/profiles between different 2D/3D CAD applications while preserving construction intent.
- PLM and data archival: Storing procedural sketch definitions in product data repositories to retain editability and traceability.
- Downstream manufacturing: Supplying accurate sketch definitions to CAM, CNC programming, tooling and simulation systems where construction history or constraints matter.
- Software development: Implementing import/export, translators, and validation tools that consume STEP-based procedural sketch data.
Who should use this standard
- CAD software vendors and developers
- PLM and data management system integrators
- Systems integrators and manufacturing engineers concerned with data exchange
- Standards implementers building STEP translators or interoperability middleware
Related standards
- ISO 10303 family (STEP) - overarching product data representation and exchange framework
- Referenced parts indicated in the document: ISO 10303-1, -11, -55, -108 (see normative references in the standard)
Keywords: ISO 10303-112:2006, procedural 2D CAD models, modelling commands, procedural sketch, STEP, product data representation and exchange, 2D CAD interoperability.