Measure assembly gaps using ray probe

Positioning mistakes can be made by a design engineer when positioning parts in an assembly. This can create contact imperfections such as excessive gaps or penetrations. Or, some penetrations can be introduced intentionally, for instance, bolt diameter usually exceeds a hole diameter due to threads.

During normal operation, Altair SimSolid’s smart contact identification automatically determines part connections. In cases where connections cannot be found, Altair SimSolid has the ray probe measurement tool for measuring part geometry and relative position in 3D space. Then, these measurements can be used to manually define connections properties between specific parts.

The measurement dialog is accessed from the main window toolbar.  Select the Ray Probe tab and then pick one or more points on the model.  Rays are cast normal to the screen through all model geometry and model segments are identified.

Below, one can see an example of how to use ray probe to evaluate gaps penetrations. There are several parts, some of them are penetrating the base solid block, some of the are at different distances off the block.


Using the ray probe, penetration and gap values are displayed in the Measurement dialog.  Selecting a value on the dialog will highlight the corresponding gap arrow on the model.


Contact gap and penetration imperfections can be a huge problem in FEA, but not for Altair SimSolid. Not only is Altair SimSolid more tolerant of tolerance settings, but problems can be easily found and remedied using the ray probe measurement tool.

Ken Welch
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Ken Welch

About Ken Welch

Ken was the cofounder and CEO at SIMSOLID corporation. He has over 30 years experience in the CAE industry in a variety of technical, sales and executive roles at companies including PDA Engineering, Rasna, Moldflow and MSC Software. Ken holds a B.S. and M.S. in civil engineering from the University of California, Davis.