I think this can be done. Please refer to Workbench User's Guide=> Working with Parameters=> Expressions, Functions, Quantities, and Units...
Why do you have to set b=zero? Won't that just cause problems during geometry creation (i.e. how do you build a gusset with zero thickness)? Wouldn't it be better to just skip building gussets whenever a= zero?
You are navigating away from the AIS Discovery experience