SN Time - Import Loadcase - Channel Mapping

Import channels and create events automatically using a .csv file.


SimSolid performs meshless structural analysis that works on full featured parts and assemblies, is tolerant of geometric imperfections, and runs in seconds to minutes. In this tutorial, you will do the following:
  • Create SN Time Fatigue loadcase.
  • Import channels and create events automatically with a .csv file.
  • Define channel mapping for events.
  • Review results.

Model Description

The following model files are needed for this tutorial:
  • SNTime-ChannelMapping.ssp
  • ChannelMapping.csv

Figure 1.
The project (.ssp) file has the following specifications:
  • Material is set to Steel for all parts.
  • Multi-loadcase workbench is included. Learn more about creating multi-loadcases here.
  • Load cases with remote loads are included.

Open Project

Open the SimSolid project file.

  1. Start a new SimSolid session.
  2. Click the (Open Project) icon.

    Figure 2.
  3. In the Open project file dialog, choose SNTime-ChannelMapping.ssp
  4. Click OK.

Review Model

Review the model and Multi-loadcase Workbench.

  1. In the Project Tree, expand the Multi-loadcases 1 Analysis Workbench.
  2. Review the loads.

    Figure 3.
  3. Click (Results plot) and choose the desired plot to review the stresses for each loadcase.

Add Fatigue Material Properties

Edit material to include fatigue properties.

If an SN curve has already been assigned, skip this step. Check the assigned material properties by right-clicking Assembly in the Project Tree and selecting Show > Materials.

  1. In the main menu, click Settings > Material database.

    Figure 4.
  2. In the dialog, click Edit current.

    Figure 5.
  3. In the Generic Materials group, right-click Steel and select Copy from the context menu.
  4. Edit the copied material.
    1. Select Steel1 - Copy_0.
    2. Click Edit material.
  5. Add fatigue curves.
    1. In the editing field of the dialog, expand the Fatigue properties branch and click Add stress-life (SN) curve....
    2. Verify the Curve definition method is set to Estimate from UTS.
  6. Click Apply.
  7. Click Save.

Create SN Time Analysis

Create SN Time Fatigue Loadcase.

  1. On the main window toolbar, click (Fatigue analysis).
  2. In the drop-down menu, select SN Time.

    Figure 6.
    The new analysis will appear in the Project Tree. The SN Time Workbench items are listed.

    Figure 7.

Import Loadcase and Channel Map

Import the loadcase and channel map from a .csv file.

  1. In the Project Tree, open the Fatigue SN/EN Time Workbench.
  2. On the workbench toolbar, click (Import loadcase-channel map).
  3. In the dialog, for Map to, verify Multi-loadcases 1 is selected.
  4. Click Set Path and pick the path for the load history files.

    Figure 8.
    These can be rsp or rpc files.
  5. Click Import from CSV and select ChannelMapping.csv.

    Figure 9.
    Note: You cannot edit the events from the dialog. Make necessary changes to the .csv file before import.
  6. Click OK.

Imported Loadcase-channel Map File Format

CSV file format for importing loadcase-channel map files.

CSV file format fields

Figure 10.
The fields in the .csv file are the same as those in the dialog.
  • Event name – Alpha-numeric values. Name of the event.
  • Repeats – Numeric values. Event repeats.
  • Gate range (optional) – Numeric values. Relative fraction of maximum gate range. The reference value is the maximum range multiplied by gate range and used for gating out small disturbances or "noise" in the time series.
  • Filename – The RSP/RPC filename. Other file formats are not supported.
  • Channel sets - The loadcase-channel map sets.
    • If empty, maps based on the order of channels and load cases. 1st loadcase is mapped to 1st channel, 2nd loadcase to 2nd channel and so on until the last loadcase/channel.
    • If there is an input in channel sets, mapping is based on the user input. For example, if the input is 2-4;6. It translates to the 1st three loadcases being mapped to channels 2 to 4, and the 4th loadcase being mapped to the 6th channel.
In this case, the input is 2:1. The 1st loadcase is mapped to the 2nd channel and the 2nd loadcase is mapped to the 1st channel. The 3rd loadcase has no mapping.

Review Channels

Review the imported channels.

  1. In the Project Tree, double-click on a channel.
    The Channel group dialog opens and lists the channels available in the load history file, along with their plots and coordinates. You can cycle between them to view the plots.
    Note: You cannot edit channels from this dialog.
    Figure 11.
  2. Optional: You can sort the plot table by Time or Amplification Factor by clicking on the column headers.
  3. Click Cancel to close the window.

Review Events

Review the imported events.

In the Project Tree, double-click on an event.
The Event setup dialog opens. You can edit channel mappings, scale, offset, gate range, and event repeats from this dialog. You can also add new Channel-loadcase mapping by clicking Add row.

Figure 12. Event 1

Figure 13. Event 2
Event 1 has default mappings as defined. Event 2 has user defined mappings; the 2nd channel is mapped to Loadcase 1 and the 1st channel is mapped to Loadcase 2.

Run Analysis

Solve the analysis.

  1. In the Project Tree, open the Analysis Workbench.
  2. Click (Solve).

Review Results

Plot fatigue damage and pick info for the fatigue subcase.

  1. In the Project Tree, Select the Fatigue SN Time 1 subcase.
  2. On the Analysis Workbench, select > Fatigue damage.
    The Legend widow opens and displays the contour plot. The Events window opens and lists all events. You can plot damage for each event or plot cumulative damage.
    Figure 14.
  3. Pick info.
    1. On the Results Workbench toolbar, click (Pick info).
    2. In the modeling window, select points of interest.
    3. In the Pick info dialog, for Event, select Total from the drop-down menu to view cumulative damage, or select the individual Event of interest.

      Figure 15.