Question $3$: Figure $3$ shows a $4-$bar mechanisms. Reference all calculated angles to the global $xY$ axes as shown in Figure $3b).$ The angle between the $x$ and $x$ axes is $25.$

a$)$ Find the angular displacement of link $4$ when link $2$ rotates clockwise from the position shown $(+37)$ to horizontal $(0).$

b$)$ How does the transmission angle vary and what is its minimum between those two positions?

c$)$ Solve for the unkowns in a$)$ by the vector loop method.

d$)$ Write a MATLAB code plot the angular position of links $3$ and $4$ and the transmission angle as a function of the angle of link $2$ as it rotates through one revolution.

rigure $3$