Geometry Input Methods

There are at least four ways to input geometries into SIMION:

1. Create the potential array (PA) file using the Modify function (Chapter 5), which is SIMION’s 3D GUI paint utility.
2. Create the PA file using geometry (GEM) files (Appendix I of SIMION 8 manual or Appendix J of SIMION 7 manual), in which constructure solid geometry (CSG) primitives are decribed in an ASCII text file. This can be done by hand or with the graphical Virtual Device utility.
3. Create the PA file from a 2D/3D CAD model, 2D raster (bitmap) image, or ASCII data file using the SL Tools in the SL Toolkit.
4. Create the PA file from a programming language via the SL Libraries in the SL Toolkit or your own code or (in 8.1 early access mode) the simion.pas interface inside SIMION.

Method #1 is useful for simpler things or to manually edit a PA file created by the other methods. It’s easiest to use for things that have cylindrical or 2D planar symmetry (i.e. surfaces of revolution or projections of 2D images) but can be used for 3D asymmetric geometries as well with a little more practice.

Method #2-4 are useful for somewhat more complicated geometries, geometries defined more mathematically, or if you need to parameterize your model (e.g. accurately rescale or quickly change dimensions on your model for testing).

Method #3-4 are useful if your model already exists in another format, whether a complex solid drawn in a third-party CAD package or a field defined in a text file or other format.

Method #3 (and Method #4 if using the SL Libraries) require SIMION® 8.0 (or the SL Toolkit for SIMION 7). Method #2 can optionally be done with Virtual Device.

See Also

• SIMION Example: geometry - various example geometries