For more information about Modal test take a look at the Modal test manual.
Modal geometry visual control is used to visualize animation of the structure. It can be found on custom control drop down menu in design mode. If the icon does not appear, the visual control Modal Geometry.vc must be added to Addons folder of Dewesoft.
Geometry can be loaded from UNV file format or Edited manually.
- Load UNV - Loads structure data from external UNV (universal file format) file
- Edit - Opens Modal Geometry editor
Mouse controls on the geometry:
- Left click: rotate structure
- Right click: translate structure
- Left+Right click: zoom
- Mouse wheel: zoom
Icons in the View section are used to enable/disable view options.
Rotate or Scale options defines what function does mouse left click (hold) and mouse movement have.
Geometry view can be selected from different perspective:
The animation can be selected in different representations:
- Color and movement
- Animate - structure will be moving/animating
- Max Shape - only max shape at a selected frequency is shown
- Manual - ucer can observe a behaviour of the strucutre with manually moving the slider inside one cycle
Scale and Speed values define how much fast and how much nodes should move. Default value for both fields is 1.
In Modal geometry, also the unmeasured points can be animated. They must be connected with a line to a measured point in order to animate them.
We do the animation of the unmeasured points with interpolation. User can manually modify the interpolation parameters.
Show original shape
By checking the Show original shape checkbox, the undeformed structure will be shown (greyed out) at the same time as deformed one.
Animation at selected frequency
Animation of the structure is done at a defined frequency. This frequency can be defined:
- From cursor channel - animated frequency is taken from yellow cursor on 2D graph
- Manual - manually define animated frequency
FRF’s calculated from the Modal test module are complex channels. They contain information about amplitude, phase, real and imaginary part. To support this, we can also animate real, imaginary or complex part.
Explanation of terms
For easier understanding, main terms are explained here.
- Object - pre-defined object in geometry (cuboid, circle, plate, …)
- Node - Node is point where sensor is positioned on object. Node is defined with location (X, Y, Z) and rotation around axes (X angle, Y angle, Z angle).
- Line - Line connects two nodes together.
- Surface - Surface can be defined with 3 or 4 nodes
- Cartesian coordinate system - Usually nodes are presented with Cartesian coordinate system. This means you have X, Y, Z position and rotation around all three axes. Coordinate system can be used for grouping nodes, because you can later rotate or translate them with Center point.
- Cylindrical coordinate system - Cylindrical coordinate system is used for easier creation of round objects. Points are defined with radius, angle and z (height) around coordinate systems center point.
The structure can be assebled from pre-defined objects. The object that are available in Geometry are:
For each object you can define the position (X, Y and Z coordinate), size (of axis) and number of points in each axis.
If the users selects option Surfaces, the surfaces will automatically be assigned to the structure.
In order to create a new strucutre from nodes, we have to switch to Nodes tab. Now we have to create coordinate system in which we will define our nodes. This can either be Cartesian or Cylindrical.
After coordinate system is created, we can add nodes with Plus button.
In the picture below, you can see Cartesian coordinate system with 18 nodes.
After nodes are created we can change their rotation (according to how sensor is rotated on object) with all three axes. Node can be selected with selection in node table or with right mouse click on structure preview window. When node is selected rotation is shown with small coordinate system located directly on node. In the picture below you can see selected and rotated node.
When node is selected, we can remove it by pressing the Minus button on nodes tab.
When nodes are defined we can go ahead and add lines to connect them.
Easiest way to create lines is to right click with the mouse on the node, select Add -> Lines.
Left click on the first node and move to the second node. This will create a white line and when you hover to the node, the line will change to green color. Select the second node and the line will be added.
You can add mulsitple lines consecutively.
Right mouse click will stop adding lines
If we don’t want to draw connected line, we can also manually add line by pressing on the Plus button in Lines tab.
With that new line added and we have to select nodes which connect them – we can do that with selecting nodes in the table.
In the picture below we can see object with some trace lines added.
Triangle surfaces can be added with a right mouse click, Add -> Triangles.
In order to add a triagle surface, 3 points must be selected as shown in the image below.
Triangle surfaces can also be added by clicking the plus button and manually define corners.
- Clear structure - the whole structure will be cleared
- Save as - save the geometry as an XML file
- Load - load existing XML file into the editor
- Import - import UNV/UFF files
- Export - the structure can be exported to UNV/UFF file format
- Exit - option will close the UNV editor and discard all your changes .
Under Tools -> Grid settings a grid can be added into the coordinate system.
User can define the position, rotation, orientation and size of the grid.
The grid is displayed in the coordinate system.
By pressing the CTRL button on the keyboard and left lick on the mouse, you can add a node to a grid.
By default, the node is set to unmeasured (green color).
Nodes state can be:
- Measured - point in the structure that we measured. The color of the point is yellow.
- Unmeasured - point in the structure that was not measured. In order to animate unmeasured points, it must be connected with a line to a measured point.
- Hidden - hidden point in the structure
- Group - group selected nodes into an object
- Ungroup - ungroup selected object into nodes
- Duplicate - duplicate selected nodes/objects
- Delete - delete selected nodes/objects
- Set anchor point to selected node - the anchor point of projection, will be placed to the selected point