Coordinate System

In the definition of an axis system, you can choose the coordinate system you want to use. Whatever the coordinate system you choose, the components are always (x,y,z).

The following topics are discussed:

Related Topics
Modifying the Axis System

Cartesian Coordinate System

The components are defined relative to a fixed rectangular coordinate system aligned with the Cartesian coordinate directions of the axis.

The axis is built locally at any point P of the support as shown below:

Cylindrical Coordinate System

The components are interpreted in a local variable rectangular coordinate system. This local coordinate system is aligned with the specified cylindrical coordinate system.

The axis is built locally at any point P of the support as shown below:


  • Uz is collinear to z, where z represents the revolution axis of a cylinder.
  • Ur and UΘ are respectively the radial and tangential components in the plane which is perpendicular to the z axis.


Spherical Coordinate System

The components are interpreted in a local variable rectangular coordinate system. This local coordinate system is aligned with the specified spherical coordinate system.

The axis is built locally at any point P of the support as shown below:

The origin of the local axis system is at the node of interest (P). So for each node of the support, a local axis is built.

Ur, UΘ and UΦ are respectively the radial, circumferential and meridional components.