KNOWLEDGE BASE // SYSML PRIMER

An Introduction to SysML

SysML is the graphical language of MBSE. It describes a system through four pillars — structure, behavior, requirements, and parametrics — using nine diagram types.

01 // THE FOUR PILLARS
STRUCTURE

What the system is

Block Definition and Internal Block diagrams describe the system's components, properties, and how they connect.

BEHAVIOR

What the system does

Activity, Sequence, State Machine, and Use Case diagrams capture function, interaction, and lifecycle behavior.

REQUIREMENTS

What the system must satisfy

Requirement diagrams trace every 'shall' statement to the design elements that satisfy and verify it.

PARAMETRICS

How the system performs

Parametric diagrams bind system properties to engineering equations for analysis and trade studies.

02 // THE NINE DIAGRAMS
BDD

Block Definition Diagram

Structure

IBD

Internal Block Diagram

Structure

PKG

Package Diagram

Structure

ACT

Activity Diagram

Behavior

SD

Sequence Diagram

Behavior

STM

State Machine Diagram

Behavior

UC

Use Case Diagram

Behavior

REQ

Requirement Diagram

Requirements

PAR

Parametric Diagram

Parametrics

In the SET Academy curriculum, you'll work hands-on with every one of these diagram types — starting with structure and requirements in Systems Modeling I, and building to full parametric analysis and simulation by Systems Modeling III.