For the shown structure, use the stochastic optimisation method of SPSA to find the

lengths of members $2$ and $3,$ which minimise the forces in links $4$ and $5.$ Note the

following constraints,

$2\mathrm{.}4m\frac{?}{b}ar(AB)3\mathrm{.}5m$ and $2\mathrm{.}8m\frac{?}{b}ar(AD)4\mathrm{.}5m$

Solve the problem for the force angle taken

as $90$deg,$120$deg and $180$ deg $.$ Note the

angle made by link $2$ with horizontal

direction for every case and comment on

the outcomes of the three runs.