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Error trying to simulate MEMS display (Constraint found for variables in different Segregated groups. Try to merge these groups.)
Posted Dec 8, 2014, 6:16 p.m. EST MEMS & Nanotechnology, MEMS & Piezoelectric Devices, Studies & Solvers Version 4.4 1 Reply
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I am working on simulating a very simple MEMS micromirror display for a class. After fighting with the Electromechanics Module for some time, I was finally able to constrain everything the way that I wanted it.
The mirror assembly with the cantilevers attached to it is supposed to be grounded, and the block under it is the terminal where I will apply voltage to bring the micromirror down.
However, when I try to solve the stationary solver, I get this error, "Constraint found for variables in different Segregated groups. Try to merge these groups.". I have no idea what this means and I have a feeling I constrained something incorrectly but I have absolutely no idea what it could be.
I've attached the model file. Any information will help.
Attachments:
Hello Ronan Rice
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The error you get means that the segregated solver implies that Comsol has split the dependent variables but your links make it coherent, so the solver proposes that you group them manually in one segregated solver. Another solution to this could be Add Fully coupled to the solver in order to automatically merge the dependent variables. Please note that in case the structure is complicated, the solver assumes constant Newton Raphson solver, in that case, changed it to Automatic (highly nonlinear). Hope it helps!