Measure minimum distance between bodies

Hxnagara

How would you measure the minimum distance between bodies. MS is obviously calculating this to check for contact, but how do I get it to report this.

Chris Coker_21312

If you are using contacts in your model, the .cof file stores the max penetration between contacts.  You can also review this graphically by loading in an automated report template, under Analysis -> View reports.  Tutorial MV-1010 provides some step by step instructions on this.

 

If your model does not have contacts, there are some techniques for doing this with the interference checking feature in HyperView.  Tutorial 'MV-5010 Rigid Body Animation - Advanced' provides you the necessary details

Hxnagara

Using the interference checking feature in Hyperview is a postprocessing function, right? If so, how I can use this in hyperstudy? Does that mean, I cannot use the minimum distance between two rigid bodies as my objective function?

Chris Coker_21312

Ok, after speaking with our developers, there is a relatively new feature/function you may want to consider: MotionSolve entity Sensor_Proximity and PROXIMITY function

 

'The Sensor_Proximity element defines a sensor between two bodies which monitors their minimum separation. The sensor tracks the state of interference of the two bodies, the minimum distance between them, and the coordinates of the pair of closest points. These quantities can be accessed using the PROXIMITY function for use in defining expressions or for plotting.'

 

The documentation for it is here:

https://altairhyperworks.com/hwhelp/Altair/2019/help/ms/topics/solvers/ms/sensor_proximity.htm

 

Some caveats from the docs:

Doesn't work with flexible bodies

Works with basic graphic primitives, and geometry that's been imported as .h3d (tria mesh).

 

 

 

Hxnagara

Thanks Chris, Will try this out a get back. I am hoping it will work on imported geometry as well.

Chris Coker_21312

As long as you are using geometry imported through the 'Import CAD/FE using Hypermesh' workflow, I think it should work.  If you are importing CAD through File -> Import Geometry, this brings in CAD (typically parasolids), this may not work.

Hxnagara

Worked like a charm! I hope it works in hyperstudy as well.