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*Local Axis System |
 
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*Local Axis System
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*Local Axis System |
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To define local axis systems.
Refer to Local (User-Defined) Axes for further information on this feature.
The keyword starts with a line defining the name of the axis system. This is then followed by a line with further entries, depending on what option is being selected. Any further axis systems or vectors can be defined by repeating the two lines as often as necessary.
Line defining the axis system name:
NAME=Axis Name
Lines defining an axis system, based on two orthogonal vectors:
X1, Y1, Z1, X2, Y2, Z2
Lines defining an axis system, based on two nodes:
Origin Node (Number or Label), LOCAL_X_NODE=Local X Node (Number or Label)
The two vectors defining an axis system must have non-zero length and must be orthogonal. If you specify a node label rather than a node number, it must be enclosed in {} brackets.
Input: |
Description |
Name: |
A unique name for the axis system being defined. |
X1: |
The component in the global X-direction of the local x-axis of the axis system being defined. See Note (a). |
Y1: |
The component in the global Y-direction of the local x-axis of the axis system being defined. See Note (a). |
Z1: |
The component in the global Z-direction of the local x-axis of the axis system being defined. See Note (a). |
X2: |
The component in the global X-direction of the local y-axis of the axis system being defined. See Notes (a) and (b). |
Y2: |
The component in the global Y-direction of the local y-axis of the axis system being defined. See Notes (a) and (b). |
Z2: |
The component in the global Z-direction of the local y-axis of the axis system being defined. See Notes (a) and (b). |
(a)If you do not specifically input a value in any of Columns 2-7, then the corresponding variable defaults to zero. Note however that all three of X1, Y1 and Z1 or all three of X2, Y2 and Z2 cannot equal zero – the null vector cannot be either the local x-axis or the local y-axis.
(b)Note that the local x-axis and local y-axis that you define here must be orthogonal, that is, the true angle between the two vectors defining the local x- and y-axes must be 90°. Flexcom will generate an error message if this is not the case, as vectors that are not orthogonal cannot be used to form a valid axis system.
Input: |
Description |
Name: |
A unique name for the axis system being defined. |
Origin Node: |
The node (number or label) at the first end of the local x axis of the axis system. If you specify a node label rather than a node number, it must be enclosed in {} brackets. |
Local X Node: |
The node (number or label) at the second end of the local x axis of the axis system. If you specify a node label rather than a node number, it must be enclosed in {} |
(a)The local x vector is formed by the straight line connecting the origin node to the local x node, and then normalised to a unit vector. The local y and local z vectors are formed automatically by Flexcom using cross products. As the local y and local z vectors are somewhat arbitrary, the node-based axis system definition is most useful when you are interested in one particular direction only. For example, if you would like to monitor out of plane displacements, you would set the local x vector to be perpendicular to the plane of interest (e.g. the rotor plane of a wind turbine).