# HyperLife Coordinate Systems

In the Contour, Iso, Tensor, and Vector panels, you can select the result coordinate system to be used to process results.

Subsequent options are dependent on the current averaging method. The available coordinate systems are:

## Global

The HyperLife default coordinate system. It is displayed in the bottom left corner of the HyperLife modeling window.

## Element

Defined from the geometry, that is, the nodal connectivity of the element. The HyperLife element coordinate systems for the following elements are described:
For Quad elements, the reader automatically selects one of the following methods:
• The origin of the coordinate system is located at the centroid of the element.
• x is along a line that bisects the angles between G2-G4 and G1-G3.
• y is perpendicular to x as shown in the figure.
• The origin of the coordinate system is located at the centroid of the element.
• x is along the G1-G2 line.
• y is perpendicular to x.
Tria3/Tria6
• The origin of the coordinate system is located at the centroid of the element.
• x is along the G1-G2 line.
• y is perpendicular to x as shown in the figure.
Hexa8/Hexa20
The element coordinate system for the Hexa element is defined in terms of the three vectors R, S, and T, which join the centroids of opposite faces, as follows:
• R vector joins the centroids of faces G4-G1-G5-G8 and G3-G2-G6-G7.
• S vector joins the centroids of faces G1-G2-G6-G5 and G4-G3-G7-G8.
• T vector joins the centroids of faces G1-G2-G3-G4 and G5-G6-G7-G8.
The origin of the coordinate system is located at the centroid of the element. The axes are derived as follows:
• z = T
• y = T x R
• x = y x z
Tetra
The element coordinate system is derived from the three vectors, R, S, and T, which join the midpoints of opposite edges, as follows:
• R vector joins midpoints of edges G1-G2 and G3-G4.
• S vector joins midpoints of edges G1-G3 and G2-G4.
• T vector joins midpoints of edges G1-G4 and G2-G3.
The origin of the coordinate system is located at the centroid of the element. The axes are derived as follows:
• z = T
• y = T x R
• x = y x z
Penta
The element coordinate system for the Penta element is derived as follows:

## Analysis

Reflects the system in which the results were defined for an element. Therefore, different elements in a model can have different systems, depending on the way they were defined in the results file. For example, a shell element can be in terms of its elemental system whereas a solid element could be in terms of the global system.

## User

A system created by the user or imported from the model file. All local coordinate systems from the model file will be imported as user systems in HyperLife.