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**1. Homework Statement**

At a particular stage of the manufacturing process, a robotic arm has the position and loading shown in the figure;

http://img246.imageshack.us/img246/5498/25481552jo0.th.png [Broken]

Calculate the direct stresses due to bending and the shear stresses due to torsion.

**2. Homework Equations**

M = r x F

**3. The Attempt at a Solution**

First, I took the applied force and resolved the moments about point A as follows (assuming the applied force is travelling parallel to the z-axis);

M = r x F = i(1-0) -j(2-0) = i - 2j

I am fairly sure that the next step in the problem is resolving these moments about the x and y axes into a moment along the figure (a torsional moment) and a moment parallel to the BC section; please refer to the following diagram;

http://img246.imageshack.us/img246/6007/72031118aw9.th.png [Broken]

However I'm not exactly sure how to do this. A tutor told me it's ok to treat the moments as if they were forces but i can't get my head around the idea.

Any advice or help would be appreciated.

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