LOOK AT THE IMAGE AND ANSWER EVERY QUESTION ASKED. Divide a plain white sheet of paper into quarters, then sketch the simplest possible model of a

screwdriver for each of the following uses:

$4.$a$.$i$-$ Load analysis $($FBD$).$ Draw the applied forces$/$torques and label any model parameters.

Describe each model parameter in $10$ words or less. Upper left quadrant.

$4.$a$.$ii $-$ First$-$order stress analysis. Draw the simple model and describe it in $10$ words or less.

Upper right quadrant.

$4.$a$.$iii $-$ More detailed stress analysis. Draw the simplest useful model and explain what type of

analysis tool you might use. Lower left quadrant.

$4.$a$.$iv $-$ Contact stresses. Draw the simplest useful model you might use and provide a brief

description. What new parameters must be included in the model? Lower right quadrant. $5.$ The above images depict a shaft and two links, loaded with vertical force Fs and supported by shafts $($not

pictured$)$ at bearings on the bottom of each link. The center shaft interacts with each link through a

bearing, which you may assume provides no resistance to rotation in the y direction but can provide

interaction moments in the x and z directions and reaction forces in all directions. Similarly, the support

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bearings cannot provide reaction moments in the y direction but can provide reactions in all other

directions. The shaft is Ls in length, as measured from bearing center to bearing center, and each link is Ll

in length, as measured from bearing center to bearing center. The load on the center shaft, Fs$,$ is centered

on the shaft in the x and y directions. The angle, $,$ of each link with respect to the z axis is $45\backslash$deg $.$

Using two$-$dimensional free body diagrams, set in either the x$-$y$,$ y$-$z or z$-$x planes, and static load analysis,

i$.$e$.,$ force and moment balance equations, determine the reaction forces and moments on the support

bearing of Link A$.$ Please give your results in terms of individual components along the x$,$ y$,$ and z axes. A

typical solution might use four individual free body diagrams to calculate the correct result.