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In this Newsletter:
How Do I Export My Raw Data?
Cut-and-Pasting Screenshots and Data from DynaMax for Windows
Measuring slowly-changing inputs (pseudo-static, below 0.1 Hz)
 
How Do I Export My Raw Data?
 
You can export raw data quite easily from DynaMax, and make an ASCII file (which Excel and other programs can easily read.)  Here's how you do it:
 
1.    Load your data file in question, then display the Wave Cursor View in DynaMax.
2.    Right-click and choose Export... (at the bottom of the resulting list.)
3.    Select File...
3.    To export only one "event", choose Between Cursors.  To export all events, choose All Non-Hidden Events.
5.    Choose your file name.  You're done!
 
You can also do this from any other view that shows a waveform.
 
Cut-and-Pasting Screenshots and Data from DynaMax for Windows
 
This is arguably the best feature DynaMax has -- interfacing with Word or Excel, you can easily cut and paste graphs and data into them with a couple of mouseclicks.  Here's how to put those graphs into Word or Excel:
 
1.    Display the graph you want.  For Scatter Plot views, make sure to use the Scatter Plot View, not the Event Selector View.
 
2.    For tabular views, click on the Invert button (upper left of the table.)  This selects all rows available.  To deselect rows, you can use the shift and control keys with the mouse button to deselect or select rows and capture any subset of the table you want.
 
3.    Right-click on the graph or on one of the event numbers displayed, and click on Copy to Clipboard.
 
4.    For Pasting cells from a DynaMax Table into Excel Only:  Open the worksheet to paste data into.  Select the cells to paste into, right click, and select Format...  Then for the Data Type select Text for all the cells.  If you don't do this, the event numbers will be scrambled up later.
 
5.    Go into Word or Excel.  Click on Edit --> Paste Special...  Select the version of pasting you want to do (paste an image, table data, etc.)  Your data or graph will now appear in your Office document!
 
Shortcut:  Just use CTRL + V to paste directly into the document.  This will usually paste the graph image, but Office will pick whatever it thinks is most appropriate.  If it doesn't paste properly, undo and start from Step 4 above to get it pasted properly.
 
Measuring slowly-changing inputs (pseudo-static, below 0.1 Hz)
 
Sometimes, you might have to measure a slowly-changing input.  Anything that you can watch transpire is usually slow enough to be concerned about.  A good example is a rollercoaster.  You can see it turn, corkscrew, and maneuver, so you must make special considerations to capture the measurement. 
 
To do this, you must have an EDR-3C, EDR-3D, MSR-3C or EDR-4 recorder, and use the internal accelerometers.  (Older recorders cannot be programmed to do such measurements, they must be modified at the factory; external accelerometers are piezoelectric and are incapable of capturing slowly-changing waveforms unless specially modified.)
 
When programming them in DynaMax, look at the Triggering Page of the setup wizard, and pay special attention to the Auto-Zero Options in the lower right corner.  The three options have different effects on your measurement:
 
Initial:  This will do the auto-zeroing of channels when the recorder first starts.  It is best to leave this on for virtually all measurements, even slowly-changing ones.
 
Between Events:  This will auto-zero while awaiting a new event to capture.  Though auto-zeroing eliminates the natural drift that sensors sometimes have, the auto-zero circuit can also eliminate the slowly-changing measurement you are trying to capture.  Therefore, turn this off for slowly-changing inputs.
 
After Trigger:  This auto-zeroes only after the trigger point begins capture of a new event.  For the same reasons as Between Events, this should also be turned off.
 
For more information on the auto-zeroing circuit inside the recorder, refer to p. 13 of the EDR-3C/EDR-3D User Manual.
 
The IST Tech Newsletter Service has been suspended indefinitely.  If you have questions about this newsletter, please send them to support@isthq.com.  We're happy to help!
 
The IST Support Staff