# Coordinate system: definition (structure)

## Definition

A coordinate system is defined by:

• a name (and a comment)
• a type of coordinate system
• a reference coordinate system (or parent coordinate system)
• the positioning of the coordinate system in the reference coordinate system

## Name

The name to identify the coordinate system is set by the user during the creation of this one.

A comment (optional) can be added to the name.

## Types of coordinate systems: 2D domain

The different types of coordinate systems and the characteristics useful for their description are gathered in the table below:

Cartesian (x,y)
Cylindrical (r,θ)
Propagated from another coordinate system

Transformation which defines the propagation

Origin coordinate system

## Types of coordinate systems: 3D domain

The different types of coordinate systems and the characteristics useful for their description are gathered in the table below:

Cartesian (x,y,z)
Cylindrical (r,θ,z)
Spherical (r,θ,φ)
Propagated from another coordinate system

Transformation which defines the propagation

Origin coordinate system

## Reference coordinate system

A coordinate system is defined with respect to a reference coordinate system (or parent coordinate system). The different reference coordinate systems are presented in the table below:

Coordinate system Description
defined with respect to the global coordinate system length unit (m, mm, µm, inch, user's unit)

defined with respect to a local coordinate system name of parent coordinate system

## Positioning: 2D domain

A coordinate system is positioned in its reference coordinate system using:

• the center coordinates of this coordinate system expressed in the reference coordinate system
• rotation angles of the axes of this coordinate system with respect to the axes of the reference coordinate system
Origin of coordinate system Rotation angle
• first component
• second component

## Positioning: 3D domain

A coordinate system is positioned in its reference coordinate system using:

• the center coordinates of this coordinate system expressed in the reference coordinate system
• rotation angles of the axes of this coordinate system with respect to the axes of the reference coordinate system
Origin of coordinate system Rotation angle
• first component
• second component
• third component