Discussion Forum

Hi,

I am using comsol 3.5a and I am having a problem defining my structure using the Matlab interface.

My model consists of ring segments. To draw them i have a function where first a 2D ring segment is drawn, which is then extruded and move to the correct position. The shape of the model depends on some design parameters
which change the positions an sizes of the segments. I am now experiencing the following:
for some sets of design parameters the program works perfectly, while for others i get the error:
"Edges are too close in 2D Domain", when drawing some of the segments.

This seems to be a bug since I found out that some times this error can be avoided when I change the order in
which the segments are drawn.
I already scaled the model from microns to meters to avoid small numbers, which did not help.
I also tried ensure the precision of the placement by rounding to the fourth decimal place, and checked
that neighboring segments use the same points at their common border. Furthermore I tried to
use geomgroup to combine the objects and varied the 'Repairtol'
option instead of combining them with '+' but that also did not help.

To find out if the error is related to the extrude operation, i wanted to get rid of that,
and create the solid object from curve3 objects by
coercing but I did not find out how or if this is possible, so maybe someone could give me a hint on that.

I would like to know if there is more information about this error since the comsol documentation is not quit
informative on that.

I also have the possibility to switch to comsol 4.0, but since the matlab interface was changed I would like
to know if migration it is worth it regarding this error.

I would be very grateful for any kinds of hints, work around and dirty hacks, to get rid of this error.
Thanks in advance
Tobias