SysML v1 ⇄ SysML v2 ⇄ Dalus Mapping

This guide maps concepts between SysML v1, SysML v2, and Dalus to help you transition your modeling knowledge.

Structural Elements

SysML v1	SysML v2	Dalus
Block / Part Property	Part Definition / Part	Part
Value Property / Value Type	Attribute Definition / Attribute	Variable
Proxy Port / Full Port	Port Definition / Port	Port
Interface Block	Interface Definition / Interface	Interface
Connector / Association Block	Connection Definition / Connection	Connection (inside Interface)

Behavioral Elements

SysML v1	SysML v2	Dalus
Action / Activity	Action Definition / Action	Action
State / State Machine	State Definition / State	State
Transition	Transition Usage	Transition
Control Flow / Object Flow	Succession	Signal

Requirements

SysML v1	SysML v2	Dalus
Requirement	Requirement Definition / Requirement	Requirement
Constraint Property	Constraint Definition / Constraint	Constraint (on Requirement)
Satisfy / Verify	Satisfy / Verification	Requirement assignment to Parts

Mission Planning

SysML v1	SysML v2	Dalus
Use Case	Use Case Definition / Use Case	Mission
Actor	Actor Definition / Actor	Actor
Subject	Subject	Subject
Include / Extend	Include / Specialization	Interaction

Diagram / View Equivalence

SysML v1 Diagram	Dalus View
Block Definition Diagram (BDD)	Part View
Internal Block Diagram (IBD)	Part View (nested into subsystems)
Activity Diagram	Action View
State Machine Diagram	State View
Use Case Diagram	Mission Planning
Requirement Diagram	Requirements Page
Parametric Diagram	Action View (with Variables)

Key Differences

Simplified Metamodel

Dalus uses a streamlined set of elements compared to full SysML. Instead of separate definition and usage concepts, Dalus elements serve both purposes contextually.

Variables Replace Value Types

Dalus Variables unify value properties, attributes, and flow properties. A Variable can be:

• An attribute on a Part
• An input/output on an Action
• A connection property on an Interface

Interfaces Contain Connections

In Dalus, an Interface groups multiple Connections together. Each Connection specifies the type (Matter, Information, Energy, Binding), direction, and properties of a single flow.

Integrated Requirements

Requirements in Dalus include Constraints that reference Variables directly. Verification status is computed automatically based on constraint evaluation—no separate verification relationships needed.

ConOps First

Dalus encourages starting with Mission Planning (Missions, Actors, Subjects) before detailed architecture, aligning with SysML v2’s emphasis on use case-driven design.