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Hello,

I am designing a MEMS actuated optical filter for WDM applications,I am designing this filter on a cantilever beam of silicon, and for actuation purpose we are using piezoelectric effect. A piezoelectric material is sandwiched in the beam. This filter is multichannel and will have a serially coupled structure of Ring Resonator arrays. When DC voltage is applied to the beam then due to the piezoelectric effect the beam will expand both in horizontal and vertical direction and due to which the refractive index of ring resonator will change. Due to which it will allow a particular signal with a certain wavelength and block the other signals. This property is used in tuning the filter. Each set of filters is located in the middle of the ring to obtain uniform stress and longitudinal uniform strain.
This beam is multilayered the beam designed below is being used for actuation purpose when DC current will be applied it will expand and due to which the upper silicon beam which consists of array of ring resonator will also expand and shape of ring resonator will change because of it and wavelength tuning will be achieved.But when I try to compute I get the below described message




Undefined variable.
- Variable: comp1.es.epsilonrmZY
- Geometry: geom1
- Domain: 45
Failed to evaluate variable.
- Variable: comp1.es.epsilonrS32
- Defined as: comp1.es.epsilonrmZY
Failed to evaluate variable.
- Variable: comp1.es.epsilonrZY
- Defined as: comp1.es.epsilonrS32
Failed to evaluate variable.
- Variable: comp1.es.chiZY
- Defined as: comp1.es.epsilonrZY
Failed to evaluate variable.
- Variable: comp1.es.PZ
- Defined as: epsilon0_const*(((comp1.es.EY*comp1.es.chiZY)+(comp1.es.EX*comp1.es.chiZX))+(comp1.es.EZ*comp1.es.chiZZ))
Failed to evaluate variable.
- Variable: comp1.es.DZ
- Defined as: comp1.es.PZ+(((comp1.spatial.detF*(comp1.es.Ey*(comp1.es.Iyy*(epsilon0_const*comp1.spatial.invF23))))+(comp1.spatial.detF*(comp1.es.Ex*(comp1.es.Ixx*(epsilon0_const*comp1.spatial.invF13)))))+(comp1.spatial.detF*(comp1.es.Ez*(comp1.es.Izz*(epsilon0_const*comp1.spatial.invF33)))))
Failed to evaluate expression.
- Expression: d(((comp1.es.DX*test(comp1.es.EX)+comp1.es.DY*test(comp1.es.EY)+comp1.es.DZ*test(comp1.es.EZ))*comp1.es.d)*(dvol),{test@12})
Failed to evaluate Jacobian of expression.
- Expression: ((comp1.es.DX*test(comp1.es.EX)+comp1.es.DY*test(comp1.es.EY)+comp1.es.DZ*test(comp1.es.EZ))*comp1.es.d)*(dvol)


I am having some problems with meshing as well.This is my final year project.Any help will be greatly appreciated.

Sincerely
Rahul Parganiha