I'm working on some stress analysis for work. I'm analyzing the design of a plate, part of which is meant to deflect under a load. Due to this sheet metal plate being somewhat non-straight forward geometry, calculating correctly is a bit tricky.(adsbygoogle = window.adsbygoogle || []).push({});

I'm putting an undercut into the plate to allow for easier deflection. Since its not one solid thickness, I didnt know if I could use a cantilever equation.

I've included pictures, one of the CAD model showing what the actual plate looks like. The other, a cross section view at the cutout (hopefully this is the correct way to analyze).

http://img210.imageshack.us/i/beam1.png/

http://img121.imageshack.us/i/beam2.png/

I would assume I could use a moment equation, and simplify it to just analyze the thinner section:

Deflection @ B due to the moment: F(A-B)B^2/2EI

However, I've been told to also sum the above with the following equations:

Deflection at B due to F translated at B: FB^3/3EI

As well as factoring in rotation:

Rotation at 'B' due to F translated at 'B': FB^2/2EI

Rotation at 'B' due to the moment of F acting at 'A': F(A-B)B/EI

Multiplying both of the above rotation equations by (A-B), you'd get "increase in deflection".

To which they said I should end up with: FB(B^2/3+A^2-AB)/EI for total deflection at 'B'.

Does this seem correct? I understand where the deflection @ B due to F translated at B equation comes from (the others I'm a bit foggy on), but I don't understand why you would sum up all of these. It seems that if you choose to use the moment to analyze the equation, you don't factor in the other equations....

Any help is appreciated.

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# Cantilever Effect on Different Thickness Plate

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