In Simcenter Testlab, the colormap display (Figure 1) is used to display a series of data in relation to a third parameter. For example, a colormap may be used to display pressure vs frequency as a function of rpm. Colormaps are extremely useful for providing insight into the causes of noise and vibration.
Figure 1: The colormap display.
This article includes tips and tricks for using colormap displays. Index:
Creating a Colormap Display
Zooming
Processing and Weighting
Processing Cursors
Order Overlay Feature
Detached Display
Rotating the Colormap
Changing Color Scale
NOTE: Functionality is similar between Simcenter Testlab and Simcenter Testlab Neo. Where there are major differences, separate instructions are given for each software version.
1. Creating a Colormap Display
To create a colormap display, press the colormap icon (Figure 2, below).
Figure 2: Colormap icons. Simcenter Testlab on left. Simcenter Testlab Neo on right.
In Simcenter Testlab, the colormap display is opened in the Navigator by pressing “Create a Picture à Colormap à OK” (highlighted in yellow). Or, the Colormap shortcut can be pressed (highlighted in red) as shown in Figure 3.
Figure 3: Open a colormap in Simcenter Testlab.
In Simcenter Testlab Neo, the colormap display is opened by pressing the “+” icon (Create a Picture) and then selecting “Colormap” as shown in Figure 4.
Figure 4: Open a colormap in Simcenter Testlab Neo.
Once the display is open, drag and drop data into the display to populate.
2. Zooming
Navigating in the colormap is made easy with the use of dynamic zooming (Figure 5):
To zoom in on an area, click and drag.
This works on the x-axis, y-axis, and z-axis.
To zoom back out, press backspace.
Figure 5: Click and drag to zoom in. Press backspace to zoom out.
This also works on two axes at once. For example, drag diagonally to zoom in two axes at once as shown in Figure 6.
Figure 6: Click and drag on the diagonal to zoom into two axes at once. Press backspace to zoom out.
Again, press backspace to zoom out.
There is lots of integrated cursor functionality in Simcenter Testlab plots. For more tips and tricks, right click on a plot and select “Mouse & Keyboard Tips…”
Figure 7: Click “Mouse & Keyboard Tips” for a list of display tips and tricks.
A full detail of the mouse and keyboard tips is available in this article.
3. Processing and Weighting
It is possible to apply processing and weighting directly to the colormap.
Right-click on the y-axis (the color scale).
Select “Processing” and then choose to either apply integration/differentiation or weighting.
Figure 8: Apply weighting and processing to the colormap.
In this case, the map is made of acoustic data, it may be useful to A-weight it. The results are shown below.
Figure 9: Colormap with A-weighting applied.
Notice that the weighting is in parenthesis near the unit format (circled in red, above).
4. Processing Cursors
The processing cursor is available on waterfalls and colormaps.
To add a processing cursor, right click on the colormap, and select “Add Processing Cursor”.
Figure 10: Add a processing cursor to a colormap.
After selecting which type of processing cursor to add, the “Cursor Processing” window will pop up.
Drag and drop the block from the cursor processing window into a display as shown in Figure 11.
Figure 11: Add a processing cursor and drag the block into a new display.
Processing cursor types include:
Z – cuts across z-axis. Often a frequency vs amplitude cut per tracking parameter (Figure 12)
Figure 12: The Z axis cut.
Order – cuts an order section out of the map (Figure 13)
Figure 13: The order cut.
Frequency – cuts per frequency. Shows how the amplitude of a frequency section changes by the tracking parameter. Has frequency section and octave section options (Figure 14).
Figure 14: Frequency and octave section cuts.
Cross – shows up as an intersection of two cursors on the map. Processing function include a z-axis cut, a frequency section, and octave section, and an order section (Figure 15).
Figure 15: Cross cursor processing options.
Note that it is possible to change the processing settings on many of the cursor options. To do so, right click on the processing block, and select “Parameters” as shown in Figure 16.
Perhaps the colormap an engineer is analyzing has complex order content from many un-correlated rotating sources. For example, some hybrid electric vehicles have internal combustion engines as well as several electric motors.
In the colormap below (Figure 17), notice that not all the order content is linearly related. This is because the order content comes from four different sources in a hybrid vehicle: two electric motors, a combustion engine, and a drive shaft.
Orders from different sources are traced in different colors (light grey, pink, red, and purple) as shown in Figure 17.
Figure 17: Colormap with order content from two uncorrelated sources.
It is also not possible to add an order cursor when the tracking value is time.
However, it may be desired to visualize different orders on this map. This may aid in determining what sources the high-vibration contributors come from.
In this example, five identical colormaps are shown in Figure 18. The tracking axis on each of the smaller maps is switched to different tacho channel.
Figure 18: The tachometer channels for the four smaller maps are changed to represent the four contributing sources (two electric motors, the combustion engine, and the driveshaft).
Watch the video below to see how the order overlays are created on the map on the right.
Note that it is also possible to drag previously calculated order content from the navigator into the map. However, users will not be able to adjust the order content like they can with processing cursors.
6. Detached Display
In Simcenter Testlab, it is possible to open a detached display, which might make viewing processing cursor results simpler.
Press the “Add a detached picture window” button.A new display area window will open.
Open a new picture in the detached display and populate it with a processing block from a processing cursor.
The detached display will update as the processing cursor is moved in the original display.
The animated gif below (Figure 19) details this process.
Figure 19: Opening and populating a detached display.
Detached displays are particularly useful when using two monitors.
7. Rotating the Colormap
It may be desired to rotate the colormap display so that the frequency axis is vertical, and the tracking axis is horizontal.
To do this (Figure 20):
Right click on the colormap, and select “Options…”.
In the “Colormap Options” window that pops up, go to the “Miscellaneous” tab.
Change the orientation from XZ to ZX.
Figure 20: Rotate the colormap by changing from XZ to ZX in the Miscellaneous tab.
After rotating, the frequency and tracking axes will be swapped as shown in Figure 21.
Figure 21: Colormap after rotating.
For cursor functionality, the frequency axis is still considered the x-axis, the amplitude axis is still the y-axis, and the tracking axis is still the z-axis.
8. Changing the Color Scale
Perhaps it is desired to change the color palate of the map. Using the right color scheme can make the colormap stand out in a report!
To do so, right click on the y-axis, select “Color Scale” and choose a new palette as shown in Figure 22.
Figure 22: Change the color palette.
Each of the color options is displayed in Figure 23, below.
Figure 23: Each of the Simcenter Testlab color palettes.