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I am trying to understand the greatly differing results between calculating the theoretical deflection of a cantilver and simulating it in ANSYS.

The cantilever is 1 um thick, 5 um wide and 300um long, one end is attached, the other end receives a force of 100uN in the y-direction (just at the end). E = 1.69e9, v = 0.066

Using E-B deflection = (4 * F * L^3)/(w * E * t^3)

The solution is ...well a lot (>1m)

In ANSYS, depending upon the meshing, etc deflection seems to be around 26-29um.

So does Euler-Bernoulli become invalid when applied to MEMS structures or when the length is much greater than the width?

is there are better way to calculate a theoretical value for the deflection?

cheers

Andrew

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# Mems cantilevers vs. Euler-Bernoulli

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