ball tolerance command


ball tolerance keyword ...

Primary keywords:

constant    extent    velocity

Set contact detection tolerances. The size of the extent with which a ball is inserted into the cell space is the minimum extent size plus twice the sum of the following quantities: 1) the maximum interaction distance; 2) the constant contact-detection tolerance (constant - default 0); 3) the maximum length of the minimum extent in all directions multiplied by the extent tolerance (extent - default \(\frac{1}{32}\)); 4) the maximum component of translational velocity multiplied by the velocity tolerance (velocity - default 0). The ball will be remapped into the cell space whenever it has translated cumulatively in any direction by this sum from the last time it was mapped into the cell space. Contacts can be created whenever the expanded extents of any pieces (i.e., balls, clump pebbles, or facets) overlap. See the description of the cycle operations “30.0 - Update Spatial Searching Data Structures” and “35.0 - Create/delete Contacts” for more details.


Directly after the model has been restored, one must call a clean prior to modifying the extent tolerances.

constant f <range>

Assign the constant contact-detection tolerance. This is assigned on a per-ball basis.

extent f

Assign the extent contact-detection tolerance. This is a global setting for all balls.

velocity f

Assign the velocity contact-detection tolerance. This is a global setting for all balls.