Overview
ISO 18629-43:2006 - part of the ISO 18629 Process Specification Language (PSL) family - defines vocabulary and definitional extensions for activity ordering and duration in the context of industrial automation and discrete manufacturing. The standard structures semantic concepts used to capture, represent and exchange process information about how activities are ordered and how long they take, enabling unambiguous communication between systems such as MES, schedulers, simulators and engineering tools.
Key topics
The document organizes definitions and grammars around consistent building blocks. Major technical topics include:
- Activity ordering models
- Strong partial orders, complex/choice posets, embedding and sequence relations
- Duration constraints
- Primitive and defined lexicons for activity duration, delays and equivalence relations
- State-based and time-based duration
- Definitions for durations tied to system state changes and calendar/time phenomena
- Mixed duration models
- Combinations of state- and time-based duration (rigid, nondeterministic, mixed)
- Ordering + duration integration
- Constraints that combine ordering relations with duration information (ordered, partial, unordered durations)
- Embedded activity constraints
- Rules for activities nested within others (embed_duration, nonembed_duration)
- Operational concerns
- Spoilage preconditions, scheduled embedding, duration-based effects, and complex sequence ordering relations
- Structured content
- Each topic provides: primitive lexicon, defined lexicon, required core theories, definitional extensions and a grammar for process descriptions
Practical applications
ISO 18629-43:2006 is used to improve interoperability and semantic clarity in applications such as:
- Production scheduling and shop-floor control (MES integration with schedulers)
- Process modeling and simulation (discrete manufacturing, digital twin models)
- Workflow engines and robotics task sequencing where precise ordering and timing matter
- Data exchange between PLM, ERP and manufacturing execution systems using a common PSL vocabulary
- Quality and safety analyses where spoilage windows and duration-based effects are critical
Implementers use the standard to encode constraints like activity durations, conditional timing, parallelism, and embedding to ensure consistent interpretation across tools.
Who should use it
- Automation and systems integrators
- Manufacturing IT architects and MES/APS vendors
- Process modelers, simulation engineers and researchers in discrete manufacturing
- Software developers implementing PSL or interoperable process exchange formats
Related standards
- ISO 18629 series (Process Specification Language / PSL) - ISO 18629-43:2006 is one part of this family, providing definitional extensions focused on activity ordering and duration for discrete manufacturing process descriptions.
Open preview (PDF)Industrial automation systems and integration — Process specification language — Part 43: Definitional extension: Activity ordering and duration extensions
